Protein biomaterials and biocoacervates and methods of making and using thereof

ABSTRACT

The present invention relates to protein biocoacervates and biomaterials and the methods of making and using protein biocoacervates and biomaterials. More specifically the present invention relates to protein biocoacervates and biomaterials that may be utilized for various medical applications including, but not limited to, drug delivery devices for the controlled release of pharmacologically active agents, coated medical devices (e.g. stents, valves . . . ), vessels, tubular grafts, vascular grafts, wound healing devices including protein suture biomaterials and biomeshes, dental plugs and implants, skin/bone/tissue grafts, tissue fillers, protein biomaterial adhesion prevention barriers, cell scaffolding and other biocompatible biocoacervate or biomaterial devices.

RELATED APPLICATIONS

This application is a division of application Ser. No. 13/435,839 filedMar. 30, 2012, which in turn is a continuation of application Ser. No.10/929,117 filed Aug. 26, 2004, which claims the benefit of U.S.Provisional Application No. 60/497,824 filed Aug. 26, 2003, each ofwhich is hereby fully incorporated herein by reference.

FIELD OF THE INVENTION

The present invention relates to protein biocoacervates and biomaterialsand the methods of making and using protein biocoacervates andbiomaterials. More specifically the present invention relates to proteinbiocoacervates and biomaterials that may be utilized for various medicalapplications including, but not limited to, drug delivery devices forthe controlled release of pharmacologically active agents, coatedmedical devices (e.g. stents, valves . . . ), vessels, tubular grafts,vascular grafts, wound healing devices including protein suturebiomaterials and biomeshes, dental plugs and implants, skin/bone/tissuegrafts, tissue fillers, protein biomaterial adhesion preventionbarriers, cell scaffolding and other biocompatible biocoacervate orbiomaterial devices.

BACKGROUND OF THE INVENTION

Protein materials are generally present in the tissues of manybiological species. Therefore, the development of medical devices thatutilize protein materials, which mimic and/or are biocompatible with thehost tissue, have been pursued as desirable devices due to theiracceptance and incorporation into such tissue. For example theutilization of protein materials to prepare drug delivery devices,tissue grafts, wound healing and other types of medical devices havebeen perceived as being valuable products due to their biocompatibilitypotential.

The use of dried protein, gelatins and/or hydrogels have previously beenused as components for the preparation of devices for drug delivery,wound healing, tissue repair, medical device coating and the like.However, many of these previously developed devices do not offersufficient strength, stability and support when administered to tissueenvironments that contain high solvent content, such as the tissueenvironment of the human body. Furthermore, the features of such medicaldevices that additionally incorporated pharmacologically active agentsoften provided an ineffective and uncontrollable release of such agents,thereby not providing an optimal device for controlled drug delivery.

A concern and disadvantage of such devices is the rapid dissolving ordegradation of the device upon entry into an aqueous or high solventenvironment. For example, gelatins and compressed dry proteins tend torapidly disintegrate and/or lose their form when placed in an aqueousenvironment. Therefore, many dried or gelatin type devices do notprovide optimal drug delivery and/or structural and durabilitycharacteristics. Also, gelatins often contain large amounts of water orother liquid that makes the structure fragile, non-rigid and unstable.It is also noted that the proteins of gelatins usually denature duringpreparation caused by heating, the gelation process and/or crosslinkingprocedures, thereby reducing or eliminating the beneficialcharacteristics of the protein. Alternatively, dried protein devices areoften very rigid, tend to be brittle and are extremely susceptible todisintegration upon contact with solvents. The deficiencies gelatins anddried matrices have with regards to rapid degradation and structurallimitations make such devices less than optimal for the controlledrelease of pharmacologically active agents, or for operating as thestructural scaffolding for devices such as vessels, stents or woundhealing implants.

Hydrogel-forming polymeric materials, in particular, have been found tobe useful in the formulation of medical devices, such as drug deliverydevices. See, e.g., Lee, J. Controlled Release, 2, 277 (1985).Hydrogel-forming polymers are polymers that are capable of absorbing asubstantial amount of water to form elastic or inelastic gels. Manynon-toxic hydrogel-forming polymers are known and are easy to formulate.Furthermore, medical devices incorporating hydrogel-forming polymersoffer the flexibility of being capable to be implantable in liquid orgelled form. Once implanted, the hydrogel forming polymer absorbs waterand swells. The release of a pharmacologically active agent incorporatedinto the device takes place through this gelled matrix via a diffusionmechanism.

However, many hydrogels, although biocompatible, are not biodegradableor are not capable of being remodeled and incorporated into the hosttissue. Furthermore, most medical devices comprising of hydrogelsrequire the use of undesirable organic solvents for their manufacture.Residual amounts of such solvents could potentially remain in themedical device, where they could cause solvent-induced toxicity insurrounding tissues or cause structural or pharmacological degradationto the pharmacologically active agents incorporated within the medicaldevice. Finally, implanted medical devices that incorporatepharmacologically active agents in general, and such implanted medicaldevices comprising hydrogel-forming polymers in particular, oftentimesprovide suboptimal release characteristics of the drug(s) incorporatedtherein. That is, typically, the release of pharmacologically activeagents from an implanted medical device that includes pharmacologicallyactive agent(s) is irregular, e.g., there is an initial burst periodwhen the drug is released primarily from the surface of the device,followed by a second period during which little or no drug is released,and a third period during which most of the remainder of the drug isreleased or alternatively, the drug is released in one large burst.

Also, particles made from decellularized tissue, such as human, bovineor porcine tissue, have also been utilized in various medicalapplications. These decellularized tissue particles have been utilizedin various applications as subcutaneous tissue fill materials.Furthermore, these substances have been shown to have some biocompatibleproperties, but generally are difficult to work with due to the alreadyestablished matrix present in such materials. Furthermore, such tissuerelated materials are not conducive to the homogenous distribution ofpharmacologically active agents within their matrix structure.

Additionally, other polymeric materials, such as polyvinyl pyrrolidone,polyvinyl alcohols, polyurethanes, polytetrafluoroethylene (PTFE),polypolyvinyl ethers, polyvinylidene halides, polyacrylonitrile,polyvinyl ketones; polyvinyl aromatics, ethylene-methyl methacrylatecopolymers, polyamides, polycarbonates, polyoxymethylenes, polyimides,polyethers and other polymeric materials have been utilized as coatingsfor medical devices, drug delivery devices, tissue fillers or grafts,sutures and for other medical applications. These materials possess somebiocompatible attributes, but are limited by their capacity to benon-thrombogenic, to be non-inflammatory, to allow direct cellintegration, to deliver therapeutic agents, to allow regeneration ofhost tissue into the graft and/or to allow other graft materials toadhere to their surface.

SUMMARY OF THE INVENTION

The present invention relates to protein biocoacervates and relatedbiomaterials and the methods of making and using protein biocoacervatesand the related biomaterials. More specifically the present inventionrelates to protein biocoacervates and related biomaterials that may beutilized for various medical applications including, but not limited to,drug delivery devices for the controlled release of pharmacologicallyactive agents, coated stent devices, vessels, tubular grafts, vasculargrafts, wound healing devices including protein suture biomaterials andbiomeshes, skin/bone/tissue grafts, tissue fillers (e.g. cosmeticwrinkle fillers), protein biomaterial adhesion prevention barriers, cellscaffolding and other biocompatible biocoacervate or biomaterialdevices.

Generally, the protein biocoacervates, related biomaterials and devicesderived from these biocoacervates or related biomaterials is anamorphous material comprising one or more biocompatible primaryproteins, one or more glycosaminoglycans and one or more biocompatiblesolvents. It is noted that the term glycosaminoglycan may also beconsidered to include mucopolysaccharides and proteoglycans.Additionally, the biocoacervates, biomaterials or their correspondingdevices may also include one or more secondary proteins, one or morepharmacologically active agents and/or one or more additive materials toprovide a therapeutic entity or enhance the chemical and/or mechanicalproperties of the biocoacervate or biomaterial.

The present invention also relates to a method of making a proteinbiocoacervate and/or biomaterial and corresponding devices. The methodof preparation includes first forming a biocompatible coacervateincluding one or more biocompatible primary proteins, one or moreglycosaminoglycans and one or more biocompatible solvents. In variousembodiments, the biocoacervate is formed by also including one or moresecondary proteins. The biocoacervate is generally assembled bycombining one or more primary proteins such as collagen, fibrin orfibronectin and one or more glycosaminoglycans such as heparin,chondroiten sulfate or heparin sulfate to a heated and optionallystirred solution of one or more biocompatible solvents such as water,DMSO, or ethanol. One or more secondary proteins such as elastin oralbumen may also be added to the primary protein/glycosaminoglycansolution. Upon adding the glycosaminoglycan to the heated solutioncontaining the primary protein(s), and in various embodiments thesecondary protein, an amorphous body falls out. The amorphous proteinbody generally falls out of the solution as an amorphous precipitatematerial allowing it to be easily extracted from the solution.Generally, the precipitant of the present invention falls out ofsolution due to a chemical and/or physical change thereby forming thewater insoluble amorphous biocoacervate. Once extracted from thesolution, the amorphous material is allowed to cool thereby forming acohesive elastic coacervate. It is noted that the material has elasticmechanical properties similar to the material utilized in rubberbandsand is capable of being melted and formed into any type shape orconfiguration. The biocoacervate is generally stable in water. However,the biocoacervate dissolves when placed in saline solution. Abiomaterial that does not dissolve in saline solution may be producedfrom the biocoacervate by setting the biocoacervate utilizing acrosslinking agent, such as gluteraldehyde, utilizing a crosslinkingtechnique like dehydrothermal processes, such as heat radiation, and/orby utilizing any crosslinking means that cause the proteins and/orglycosaminoglycans to crosslink.

As previously mentioned, the biocoacervate or biomaterial may alsooptionally include additional polymeric materials and/or therapeuticentities, such as one or more pharmacologically active agents, thatwould provide additional beneficial characteristics or features to thecoacervate. Generally, these materials and/or entities may be added tothe solution during the formation of the coacervate. Alternatively,these materials and/or entities may be added after the coacervate hasbeen formed utilizing any means to disperse the agent(s) within thebiocoacervate such as dissolving the agent(s) into the melted form ofthe coacervate or allowing diffusion and/or loading the agent(s) intothe unmelted coacervate.

The above described process has many advantages if one or morepharmacologically active agents are incorporated into the biocoacervate.For example, the controlled release characteristics of thebiocoacervates and biomaterials of the present invention provide for ahigher amount of pharmacologically active agent(s) that may beincorporated into the biocoacervate or biomaterial. Additionally, thepharmacologically active agent(s) may be substantially homogeneouslydistributed throughout biocoacervate, biomaterial or correspondingdevices. This homogenous distribution provides for a more systematic andconsistent release of the pharmacologically active agent(s). As aresult, the release characteristics of the pharmacologically activeagent from the biocoacervate, biomaterial and/or device are enhanced.

Inasmuch as the biocoacervates, biomaterials and corresponding devicesof the present invention provide the sustained release of one or morepharmacologically active agents in a rate controllable fashion, they arealso capable of delivering other migration-vulnerable and/or reactivedrug delivery devices and furthermore are produced in a manner thatreduces, if not eliminates, the risk of residual solvent toxicity oradverse tissue reaction. Also, the biocoacervates, biomaterials andcorresponding devices of the present invention provide a method ofeffecting a local therapeutic response in a patient in need of suchtreatment. Specifically, the method of using the biocoacervate,biomaterial or related devices of the present invention comprises thestep of administering the biocoacervate, biomaterial or correspondingdevice to the site at which a local therapeutic response is desired.Additionally, the biocoacervates, biomaterials and corresponding devicesmay be administered for systemic delivery of pharmacologically activeagents, including oral, as well as nasal, mucosal, intraocularpulmonary, subcutaneous, intradermal, intrathecal, sublingual, epidural,subdural, tissue implantable or any other parenteral mode of delivery.Preferably, the therapeutic response effected is an analgesic response,an anti-inflammatory response, an anesthetic response, a responsepreventative of an immunogenic response, an anti-coagulatory response, agenetic response, an antimitotic response, a protein assembly response,an antibacterial response, a vaccination response, combinations ofthese, and the like. As used herein, unless stated otherwise, allpercentages are percentages based upon the total mass of the compositionbeing described, e.g., 100% is total.

The foregoing and additional advantages and characterizing features ofthe present invention will become increasingly apparent to those ofordinary skill in the art by references to the following detaileddescription and to the drawings.

BRIEF DESCRIPTION OF THE FIGURES

The above mentioned and other advantages of the present invention, andthe manner of attaining them, will become more apparent and theinvention itself will be better understood by reference to the followingdescription of the embodiments of the invention taken in conjunctionwith the accompanying drawing, wherein:

FIG. 1 depicts a magnified view of an embodiment of the biomaterial ofthe present invention illustrating the aggregated proteoids;

FIG. 2A-C depicts a magnified view of an embodiment of the biomaterialof the present invention illustrating the aggregated proteoids;

FIG. 3 depicts one embodiment of the biocoacervate of the presentinvention cut into a square shape;

FIG. 4A depicts one embodiment of the particles of the presentinvention;

FIG. 4B depicts one embodiment of a particle of the present inventionillustrated using frozen sample scanning electron microscopy;

FIG. 5 depicts one embodiment of the particles of the present inventionwherein a slurry of particles and saline are delivered through a 27guage needle;

FIG. 6 depicts a biomaterial drug delivery device that include releasemechanisms contained in the biomaterial;

FIG. 7 is a schematic illustration, in partial cross-sectional view, ofa compression molding device that may be used in the method of thepresent invention in wherein the inner insert includes a mandrel that isengaged with a stent;

FIG. 8 depicts an embodiment of a polypropylene/polytetrafluoroethylenescaffolding structure before applying the biocoacervate of the presentinvention;

FIGS. 9A-C, depict an embodiment of apolypropylene/polytetrafluoroethylene tube that is coated andimpregnated with the biocoacervate of the present invention;

FIGS. 10A-B depict magnified cross-sectional views of one embodiment ofa vessel of the present invention wherein the scaffolding material is apolyurethane foam;

FIGS. 11A-B depict another embodiment of a vessel of the presentinvention that has been implanted and wherein the scaffolding materialis a cotton knit;

FIG. 12A-B depicts an embodiment of a tube made of the biomaterial ofthe present invention wherein endothelial cells are present on thesurface of the biomaterial;

FIG. 13 depicts an embodiment of a compression molding device whereinthe inner insert includes a mandrel;

FIG. 14 depicts the top view of an embodiment of the compression moldingdevice without the upper insert or plunger;

FIG. 15 depicts one embodiment of a vessel prepared by compressingparticles of collagen/elastin/heparin and allowing the compressedparticles to dry thereby setting the tublar configuration;

FIG. 16 depicts an embodiment of a wound healing device comprising aprotein matrix that is positioned in the center of a non-adhesive stripof material attached to two adhesive ends;

FIG. 17 depicts an embodiment of a bilaminar dressing that includes anEpithelial Cell Migration layer, a Fibroblast/Endothelial Infiltrationlayer and particles; and

FIG. 18 depicts an embodiment of a protrusion device 34 that includes aport seal.

DETAILED DESCRIPTION OF THE INVENTION

The embodiments of the invention described below are not intended to beexhaustive or to limit the invention to the precise forms disclosed inthe following detailed description. Rather, the embodiments are chosenand described so that others skilled in the art may appreciate andunderstand the principles and practices of the present invention.

The biocoacervates, biomaterials and devices of the present inventioncomprise an amorphous material that generally includes one or moreprimary proteins, one or more glycosaminoglycans and one or morebiocompatible solvents. The amorphous material of the present inventiontends to have no real or apparent crystalline or fibrous form that canbe seen by the naked eye or by light microscope at 400.times. or less.Such materials are different from other protein and glycosaminoglycanmaterials, which tend to be crystalline, fibrous or appears similar toballs of yarn. Also the biocoacervate and a number of the biomaterialembodiments of the present invention tend to have thermoplastic andviscoelastic properties. In various embodiments of the present inventionthe biocoacervates, biomaterials and devices may also include one ormore secondary proteins.

FIGS. 1 and 2A-B depict a magnified view of embodiments of thebiomaterials of the present invention. As depicted in these figures,various embodiments of the biocoacervate of the present inventioninclude a plurality of individual spherical complexes (hereinafterreferred to as “proteoids”), which interact with each other to form thebiocoacervate. Generally, the proteoids found in the present inventionare small microspheres comprising at least a primary protein, aglycosaminoglycan and a biocompatible solvent. The proteoids will tendto aggregate together to form the amorphous biocoacervate embodiments ofthe present invention. Also, it has been found that under certainconditions the proteoids can undergo strong intermolecular bonding thatmay alter their shape. FIG. 2C depicts an embodiment of thebiocoacervate that has been crosslinked and freeze fractured toillustrate that the proteoids of this embodiment include inner cavitiesand crosslinks that hold the proteoids together into a single mass.These proteoids or spherical complexes generally range from 0.001 to 100microns in size, in various embodiments 0.1 to 10 microns, but may varyin size depending upon the amount of swelling they experience. Theswelling of biocoacervates including the proteoids may be controlled bycrosslinking, pH, compression, salt content, solvent content (e.g. wateror alcohol content) and/or temperature. Furthermore, the amount ofswelling may be controlled by adjusting the various degrees ofcrosslinking of the biocoacervate before exposing the material to one ormore solutions.

Additionally, embodiments of the biocoacervates, biomaterials anddevices of the present invention may also include one or moretherapeutic pharmacologically active agents and/or one or more additivematerials, such as structural or polymeric materials. It is noted thatadditional additive materials, such as humectants, biocompatiblepolymers (e.g. proteins, polyanhydride, polylactic acid, polyurethaneand the like) and/or therapeutic entities, such as stents and othermedical devices may be included in the material to provide variousbeneficial features such as mucoadhesion, strength, elasticity,structure, enhanced biocompatibility, enhanced drug delivery and drugabsorption, therapeutic functions or any other desirablecharacteristics. In various embodiments of the present invention, thebiocoacervates or biomaterials possess a relatively homogeneousdistribution of the components, including a homogenous distribution ofany pharmacologically active agents and additive materials.

The biocoacervates, biomaterials and the related devices of the presentinvention are designed to retain the protein's natural activity andpossess the capability of being formed into various sizes andconfigurations with structural integrity. Embodiments of thebiocoacervates, biomaterials and the related devices are furtherdesigned to mimic the architectural framework of the body to supportnatural tissue growth. In various embodiments of the present inventionthe biocoacervates, biomaterials and the related devices of the presentinvention are biointegratable thereby allowing the integration andremodeling of the material by the host tissue.

As previously mentioned, the biocoacervates, biomaterials and therelated devices normally comprise one or more biocompatible primaryproteins and, in various embodiments, one or more secondary proteins.The primary and secondary proteins are generally soluble or aresolubilized. Primary proteins normally have an affinity to bind withglycosaminoglycans and in some instances other proteins therebyindicating that functional groups are present on the primary proteinsthat attract and retain the glycosaminoglycans and possibly otherproteins. Additionally, primary proteins when mixed withglycosaminoglycans in solution under proper conditions will generallyform a precipitate that falls out of solution, whereas the secondaryproteins will not form such a precipitate when placed in solution withglycosaminoglycans. Additionally, secondary proteins generally have amore limited binding affinity with glycosaminoglycans than their primaryprotein counterparts, but are attracted and retained by the primaryproteins in the presence of glycosaminoglycans. However, secondaryproteins have been found to add very beneficial characteristics to thebiocoacervates of the present invention, such as elasticity, strength,biodurability, biocompatibility and the like. Generally, the amount ofprimary protein found in embodiments of the biocoacervate orbiomaterials of the present invention may vary between from about 10% toabout 90%, preferably from about 20% to 80% by weight, and mostpreferably from about 50% to 70% by weight based upon the weight of thefinal biocoacervate or biomaterial. Alternatively, the amount ofsecondary protein may vary between from about 0% to about 40%,preferably from about 10% to 30% by weight, and most preferably fromabout 15% to 25% by weight based upon the weight of the finalbiocoacervate or biomaterial.

The primary and secondary proteins utilized in the present invention maybe synthetic proteins, genetically-engineered proteins, natural proteinsor any combination thereof. In many embodiments of the presentinvention, the biocoacervates, biomaterials and the related devicesinclude water-absorbing, biocompatible primary and secondary proteins.The utilization of a water-absorbing biocompatible protein included inthe biocoacervate or biomaterial provides the advantage that, not onlywill the biocoacervates or biomaterials be bioresorbable, but mayremodel to mimic and support the tissue it contacts. That is, themetabolites of any degradation and/or resorption of the water-absorbingbiocompatible protein may be reused by the patient's body rather thanexcreted.

Additionally, the primary and secondary proteins of the presentinvention are generally purified and in a free-form state. Normally,free-form proteins are comprised of protein molecules that are notsubstantially crosslinked to other protein molecules, unlike tissues(e.g. decellularized tissue) or gelatins. Normally, tissue or gelatin isalready in a crosslinked matrix form and is thereby limited in formingnew intermolecular or intramolecular bonds. Therefore, the free-formprotein molecules when added to solvent have the capacity to freelyassociate or intermingle with each other and other molecules orparticles, such as solvents, pharmacologically active agents, additivesand other proteins to form a homogeneous structure. Additionally, thebinding sites of the free-form primary proteins for the attraction andretention of glycosaminoglycans or secondary proteins are generallyavailable for binding whereas proteins derived from tissues and gelatinshave generally lost some or most of its binding or interactioncapability.

As previously suggested, the primary and secondary proteins utilized mayeither be naturally occurring, synthetic or genetically engineered.Naturally occurring primary proteins that may be utilized inbiocoacervates, biomaterials and related devices of the presentinvention include, but are not limited to the following and theirderivatives: collagen, bone morphogenic protein and its isoforms thatcontain glucosaminoglycan binding sites, albumin, interleukins,epidermal growth factors, fibronectin, laminin, thrombin, aprotinin,antithrombin III and any other biocompatible natural protein thatincludes glucosaminoglycan binding sites. Naturally occurring secondaryproteins that may be utilized in biocoacervates, biomaterials andrelated devices of the present invention include, but are not limited tothe following and their derivatives: fibrin, fibrinogen, elastin,albumin, ovalbumin, keratin, silk, silk fibroin, actin, myosin,thrombin, aprotinin, antithrombin III and any other biocompatiblenatural protein that have an affinity to primary proteins in thepresence of glucosaminoglycans. Examples of primary and secondaryproteins that are commercially available and may be utilized in someembodiments of the present invention include Type I soluble or insolublecollagen, insoluble or soluble elastin, and soluble albumen manufacturedby Kensey Nash Corporation, 55 East Uwchlan Avenue, Exton, Pa. 19341,Sigma-Aldrich Corporation, St. Louis, Mo., USA or Elastin ProductsCompany, Inc., P.O. Box 568, Owensville, Mo., USA 65066. It is notedthat in various embodiments of the present invention, the insolubleproteins listed above would be processed to a soluble form prior to orduring synthesis of a biocoacervate or biomaterial. It is further notedthat combinations of natural proteins may be utilized to optimizedesirable characteristics of the resulting biocoacervates andbiomaterials, such as strength, degradability, resorption, etc. Inasmuchas heterogeneity in molecular weight, sequence and stereochemistry caninfluence the function of a protein in a biocoacervate or biomaterial,in some embodiments of the present invention synthetic or geneticallyengineered proteins are preferred in that a higher degree of control canbe exercised over these parameters.

As previously suggested the primary and secondary proteins of thepresent invention are generally purified proteins. The purity of eachnatural protein component mixed in the solution phase (the process ofmaking the coacervates and biomaterials will be described further below)during production of the coacervate include 20% or less other proteinsor impurities, preferably 10% or less other proteins or impurities, morepreferably 3% or less other proteins or impurities and if availableideally 1% or less other proteins or impurities.

Synthetic primary and secondary proteins are generally prepared bychemical synthesis utilizing techniques known in the art and generallymimic the equivalent natural protein's or natural protein derivative'schemical and/or structural makeup. Furthermore, individual proteins maybe chemically combined with one or more other proteins of the same ordifferent type to produce a dimer, trimer or other multimer. A simpleadvantage of having a larger protein molecule is that it will makeinterconnections with other protein molecules to create a strongercoacervate or biomaterial that is less susceptible to dissolving inaqueous solutions and provides additional protein structural andbiochemical characteristics.

Additionally, protein molecules can also be chemically combined to anyother chemical so that the chemical does not release from thebiocoacervate or biomaterial. In this way, the chemical entity canprovide surface modifications to the biocoacervate or biomaterial orstructural contributions to the biocoacervate or biomaterial to producespecific characteristics. The surface modifications can enhance and/orfacilitate cell attachment depending on the chemical substance or thecell type. The structural modifications can be used to facilitate orimpede dissolution or enzymatic degradation of the biocoacervate orbiomaterial, as well as increase the affinity of the biocoacervate tointeract (e.g. bind or coat) with other materials.

Synthetic biocompatible proteins may be cross-linked, linked, bonded,chemically and/or physically linked to pharmacological active agents,enzymatically, chemically or thermally cleaved and utilized alone or incombination with other biocompatible proteins or partial proteins e.g.peptides, to form the biocoacervates or biomaterials. Examples of suchsynthetic biocompatible proteins include, but are not limited toheparin-protein, heparin-polymer, chondroitin-protein,chondroitin-polymer, heparin-cellulose, heparin-alginate,heparin-polylactide, GAGs-collagen, heparin-collagen,collagen-elastin-heparin, collagen-albumin, collagen-albumin-heparin,collagen-albumin-elastin-heparin, collagen-hyaluronic acid,collagen-chondroitin-heparin, collagen-chondroitin and the like.

A specific example of a particularly preferred genetically engineeredprimary protein for use in the biocoacervates or biomaterials of thepresent invention is human collagen produced by FibroGen, Inc., 225Gateway Blvd., South San Francisco, Calif. 94080. Other examples ofparticularly preferred genetically engineered proteins for use in thebiocoacervates or biomaterials of the present invention are commerciallyavailable under the nomenclature “ELP”, “SLP”, “CLP”, “SLPL”, “SLPF” and“SELP” from Protein Polymer Technologies, Inc. San Diego, Calif. ELP's,SLP's, CLP's, SLPL's, SLPF's and SELP's are families of geneticallyengineered protein polymers consisting of silklike blocks, elastinlikeblocks, collagenlike blocks, lamininlike blocks, fibronectinlike blocksand the combination of silklike and elastinlike blocks, respectively.The ELP's, SLP's, CLP's, SLPL's, SLPF's and SELP's are produced invarious block lengths and compositional ratios. Generally, blocksinclude groups of repeating amino acids making up a peptide sequencethat occurs in a protein. Genetically engineered proteins arequalitatively distinguished from sequential polypeptides found in naturein that the length of their block repeats can be greater (up to severalhundred amino acids versus less than ten for sequential polypeptides)and the sequence of their block repeats can be almost infinitelycomplex. Table A depicts examples of genetically engineered blocks.Table A and a further description of genetically engineered blocks maybe found in Franco A. Ferrari and Joseph Cappello, Biosynthesis ofProtein Polymers, in: Protein-Based Materials, (eds., Kevin McGrath andDavid Kaplan), Chapter 2, pp. 37-60, Birkhauser, Boston (1997).

TABLE A  Protein polymer sequences Polymer  NameMonomer Amino Acid Sequence SLP 3 [(GAGAGS)₉GAAGY)] SLP 4 (GAGAGS)_(n)SLP F [(GAGAGS)₉GAA VTGRGDSPAS AAGY]_(n) SLP L3.0[(GAGAGS)₉GAA PGASIKVAVSAGPS AGY]_(n) SLP L3.1[(GAGAGS)₉GAA PGASIKVAVSGPS AGY]_(n) SLP F9[(GAGAGS)₉RYVVLPRPVCFEK AAGY]_(n) ELP I [(VPGVG)₄]_(n) SELP 0[GVGVP)₈(GAGAGS)₂]_(n) SELP 1 [GAA(VPGVG)₄VAAGY(GAGAGS)₉]_(n) SELP 2[(GAGAGS)₆GAAGY(GAGAGS)₅(GVGVP)₈]_(n) SELP 3 [GVGVP)₈(GAGAGS)₈]_(n)SELP 4 [GVGVP)₁₂(GAGAGS)₈]_(n) SELP 5 [GVGVP)₁₆(GAGAGS)₈]_(n) SELP 6[GVGVP)₃₂(GAGAGS)₈]_(n) SELP 7 [GVGVP)₈(GAGAGS)₆]_(n) SELP 8[GVGVP)₈(GAGAGS)₄]_(n) KLP 1.2 [(AKLKLAEAKLELAE)₄]_(n) CLP 1[GAP(GPP)₄]n CLP 2 {[GAP(GPP)₄]₂GPAGPVGSP}_(n) CLP-CB{[GAP(GPP)₄]₂(GLPGPKGDRGDAGPKGADGSPGPA) GPAGPVGSP}_(n) CLP 3(GAPGAPGSQGAPGLQ)_(n) Repetitive amino acid sequences of selectedprotein polymers. SLP = silk like protein; SLPF = SLP containing the RGDsequence from fibronectin; SLPL 3/0 and SLPL 3/1 = SLP containing twodifference sequences from laminin protein; ELP = elastin like protein;SELP = silk elastin like protein; CLP = collagen like protein; CLP-CB =CLP containing a cell binding domain from human collagen; KLP = keratinlike protein

The nature of the elastinlike blocks, and their length and positionwithin the monomers influences the water solubility of the SELPpolymers. For example, decreasing the length and/or content of thesilklike block domains, while maintaining the length of the elastinlikeblock domains, increases the water solubility of the polymers. For amore detailed discussion of the production of SLP's, ELP's, CLP's,SLPF's and SELP's as well as their properties and characteristics see,for example, in J. Cappello et al., Biotechnol. Prog., 6, 198 (1990),the full disclosure of which is incorporated by reference herein. Onepreferred SELP, SELP7, has an elastin:silk ratio of 1.33, and has 45%silklike protein material and is believed to have weight averagemolecular weight of 80,338.

The biocoacervates and biomaterials utilized in various embodiments ofthe present invention also include one or more glycosaminoglycans,proteoglycans or mucopolysaccharides.

Glycosaminoglcans can be derived or synthesized from any source,including artificial, animal or plant sources. Examples ofglycosaminoglycans that are utilized in the coacervates and biomaterialsof the present invention include but are not limited to the heparin,heparin sulfate, keratan sulfate, dermatin, dermatin sulfate,heparin-hyaluronic acid, chondroitin, chondroitin sulfate (e.g.chondroitin 6-sulfate and chondroitin 4-sulfate), chitin, chitosan,acetyl-glucosamine, hyaluronic acid, aggrecan, decorin, biglycan,fibromodulin, lumican, combinations, glycosaminoglycan complexes orcompounds and the like.

The biocoacervates and biomaterials utilized in various embodiments ofthe present invention also include one or more biocompatible solvents.Any biocompatible solvent may be utilized in the method andcorresponding coacervate or biomaterial of the present invention. Byusing a biocompatible solvent, the risk of adverse tissue reactions toresidual solvent remaining in the device after manufacture is minimized.Additionally, the use of a biocompatible solvent reduces the potentialstructural and/or pharmacological degradation of the pharmacologicallyactive agent that some such pharmacologically active agents undergo whenexposed to organic solvents. Suitable biocompatible solvents for use inthe method of the present invention include, but are not limited to,water; dimethyl sulfoxide (DMSO); biocompatible alcohols, such aspolyols, glycerol, methanol and ethanol; various acids, such as aceticacid, citric acid, ascorbic acid and formic acid; oils, such as oliveoil, peanut oil and the like; glycols, such as ethylene glycol; andcombinations of these and the like. Preferably, the biocompatiblesolvent comprises water. The amount of biocompatible solvent utilized inthe formation of the present invention will preferably be that amountsufficient to result in the primary and secondary proteins being fluidand flowable enough to allow the protein to enter into solution.Generally, the amount of biocompatible solvent suitable for use in themethod of the present invention will range from about 100% to about50,000% by weight, in some embodiments from about 200% to about 10,000%by weight, and in other embodiments from about 300% to about 2000% byweight, based upon the weight and/or amount of the protein utilized.

In addition to the biocompatible protein(s) and the biocompatiblesolvent(s), the coacervates or biomaterial that may be utilized invarious embodiments of the present invention may include one or morepharmacologically active agents. Generally, the distribution of thepharmacologically active agent is rendered substantially homogenousthroughout the resulting coacervate or biomaterial. As used herein,“pharmacologically active agent” generally refers to a pharmacologicallyactive agent having a direct or indirect beneficial therapeutic effectupon introduction into a host. Pharmacologically active agents furtherincludes neutraceuticals. The phrase “pharmacologically active agent” isalso meant to indicate prodrug forms thereof. A “prodrug form” of apharmacologically active agent means a structurally related compound orderivative of the pharmacologically active agent which, whenadministered to a host is converted into the desired pharmacologicallyactive agent. A prodrug form may have little or none of the desiredpharmacological activity exhibited by the pharmacologically active agentto which it is converted. Representative examples of pharmacologicallyactive agents that may be suitable for use in the coacervates,biomaterials and related devices of the present invention include, butare not limited to, (grouped by therapeutic class):

Antidiarrhoeals such as diphenoxylate, loperamide and hyoscyamine;

Antihypertensives such as hydralazine, minoxidil, captopril, enalapril,clonidine, prazosin, debrisoquine, diazoxide, guanethidine, methyldopa,reserpine, trimethaphan;

Calcium channel blockers such as diltiazem, felodipine, amlodipine,nitrendipine, nifedipine and verapamil;

Antiarrhyrthmics such as amiodarone, flecamide, disopyramide,procainamide, mexiletene and quinidine;

Antiangina agents such as glyceryl trinitrate, erythrityl tetranitrate,pentaerythritol tetranitrate, mannitol hexanitrate, perhexylene,isosorbide dinitrate and nicorandil;

Beta-adrenergic blocking agents such as alprenolol, atenolol,bupranolol, carteolol, labetalol, metoprolol, nadolol, nadoxolol,oxprenolol, pindolol, propranolol, sotalol, timolol and timolol maleate;

Cardiotonic glycosides such as digoxin and other cardiac glycosides andtheophylline derivatives;

Adrenergic stimulants such as adrenaline, ephedrine, fenoterol,isoprenaline, orciprenaline, rimeterol, salbutamol, salmeterol,terbutaline, dobutamine, phenylephrine, phenylpropanolamine,pseudoephedrine and dopamine;

Vasodilators such as cyclandelate, isoxsuprine, papaverine,dipyrimadole, isosorbide dinitrate, phentolamine, nicotinyl alcohol,co-dergocrine, nicotinic acid, glycerl trinitrate, pentaerythritoltetranitrate and xanthinol;

Antiproliferative agents such as paclitaxel, actinomycin D, sirolimus,tacrolimus, everolimus, estradiol and dexamethasone;

Antimigraine preparations such as ergotanmine, dihydroergotamine,methysergide, pizotifen and sumatriptan;

Anticoagulants and thrombolytic agents such as warfarin, dicoumarol, lowmolecular weight heparins such as enoxaparin, streptokinase and itsactive derivatives;

Hemostatic agents such as aprotinin, tranexamic acid and protamine;

Analgesics and antipyretics including the opioid analgesics such asbuprenorphine, dextromoramide, dextropropoxyphene, fentanyl, alfentanil,sufentanil, hydromorphone, methadone, morphine, oxycodone, papaveretum,pentazocine, pethidine, phenopefidine, codeine dihydrocodeine;acetylsalicylic acid (aspirin), paracetamol, and phenazone;

Immunosuppressants, antiproliferatives and cytostatic agents such asrapomycin (sirolimus) and its analogs (everolimus and tacrolimus);

Neurotoxins such as capsaicin, botulinum toxin (botox);

Hypnotics and sedatives such as the barbiturates amylobarbitone,butobarbitone and pentobarbitone and other hypnotics and sedatives suchas chloral hydrate, chlormethiazole, hydroxyzine and meprobamate;

Antianxiety agents such as the benzodiazepines alprazolam, bromazepam,chlordiazepoxide, clobazam, chlorazepate, diazepam, flunitrazepam,flurazepam, lorazepam, nitrazepam, oxazepam, temazepam and triazolam;

Neuroleptic and antipsychotic drugs such as the phenothiazines,chlorpromazine, fluphenazine, pericyazine, perphenazine, promazine,thiopropazate, thioridazine, trifluoperazine; and butyrophenone,droperidol and haloperidol; and other antipsychotic drugs such aspimozide, thiothixene and lithium;

Antidepressants such as the tricyclic antidepressants amitryptyline,clomipramine, desipramine, dothiepin, doxepin, imipramine,nortriptyline, opipramol, protriptyline and trimipramine and thetetracyclic antidepressants such as mianserin and the monoamine oxidaseinhibitors such as isocarboxazid, phenelizine, tranylcypromine andmoclobemide and selective serotonin re-uptake inhibitors such asfluoxetine, paroxetine, citalopram, fluvoxamine and sertraline;

CNS stimulants such as caffeine and 3-(2-aminobutyl)indole;

Anti-alzheimer's agents such as tacrine;

Anti-Parkinson's agents such as amantadine, benserazide, carbidopa,levodopa, benztropine, biperiden, benzhexyl, procyclidine and dopamine-2agonists such asS(−)-2-(N-propyl-N-2-thienylethylamino)-5-hydroxytetralin (N-0923);

Anticonvulsants such as phenyloin, valproic acid, primidone,phenobarbitone, methylphenobarbitone and carbamazepine, ethosuximide,methsuximide, phensuximide, sulthiame and clonazepam;

Antiemetics and antinauseants such as the phenothiazinesprochloperazine, thiethylperazine and 5HT-3 receptor antagonists such asondansetron and granisetron, as well as dimenhydrinate, diphenhydramine,metoclopramide, domperidone, hyoscine, hyoscine hydrobromide, hyoscinehydrochloride, clebopride and brompride;

Non-steroidal anti-inflammatory agents including their racemic mixturesor individual enantiomers where applicable, preferably which can beformulated in combination with dermal and/or mucosal penetrationenhancers, such as ibuprofen, flurbiprofen, ketoprofen, aclofenac,diclofenac, aloxiprin, aproxen, aspirin, diflunisal, fenoprofen,indomethacin, mefenamic acid, naproxen, phenylbutazone, piroxicam,salicylamide, salicylic acid, sulindac, desoxysulindac, tenoxicam,tramadol, ketoralac, flufenisal, salsalate, triethanolamine salicylate,aminopyrine, antipyrine, oxyphenbutazone, apazone, cintazone, flufenamicacid, clonixerl, clonixin, meclofenamic acid, flunixin, coichicine,demecolcine, allopurinol, oxypurinol, benzydamine hydrochloride,dimefadane, indoxole, intrazole, mimbane hydrochloride, paranylenehydrochloride, tetrydamine, benzindopyrine hydrochloride, fluprofen,ibufenac, naproxol, fenbufen, cinchophen, diflumidone sodium, fenamole,flutiazin, metazamide, letimide hydrochloride, nexeridine hydrochloride,octazamide, molinazole, neocinchophen, nimazole, proxazole citrate,tesicam, tesimide, tolmetin, and triflumidate;

Antirheumatoid agents such as penicillamine, aurothioglucose, sodiumaurothiomalate, methotrexate and auranofin;

Muscle relaxants such as baclofen, diazepam, cyclobenzaprinehydrochloride, dantrolene, methocarbamol, orphenadrine and quinine;

Agents used in gout and hyperuricaemia such as allopurinol, colchicine,probenecid and sulphinpyrazone;

Oestrogens such as oestradiol, oestriol, oestrone, ethinyloestradiol,mestranol, stilboestrol, dienoestrol, epioestriol, estropipate andzeranol;

Progesterone and other progestagens such as allyloestrenol,dydrgesterone, lynoestrenol, norgestrel, norethyndrel, norethisterone,norethisterone acetate, gestodene, levonorgestrel, medroxyprogesteroneand megestrol;

Antiandrogens such as cyproterone acetate and danazol;

Antioestrogens such as tamoxifen and epitiostanol and the aromataseinhibitors, exemestane and 4-hydroxy-androstenedione and itsderivatives;

Androgens and anabolic agents such as testosterone, methyltestosterone,clostebol acetate, drostanolone, furazabol, nandrolone oxandrolone,stanozolol, trenbolone acetate, dihydro-testosterone,17-(α-methyl-19-noriestosterone and fluoxymesterone;

5-alpha reductase inhibitors such as finasteride, turosteride, LY-191704and MK-306;

Corticosteroids such as betamethasone, betamethasone valerate,cortisone, dexamethasone, dexamethasone 21-phosphate, fludrocortisone,flumethasone, fluocinonide, fluocinonide desonide, fluocinolone,fluocinolone acetonide, fluocortolone, halcinonide, halopredone,hydrocortisone, hydrocortisone 17-valerate, hydrocortisone 17-butyrate,hydrocortisone 21-acetate, methylprednisolone, prednisolone,prednisolone 21-phosphate, prednisone, triamcinolone, triamcinoloneacetonide;

Complex carbohydrates such as glucans;

Further examples of steroidal anti-inflammatory agents such ascortodoxone, fludroracetonide, fludrocortisone, difluorsone diacetate,flurandrenolone acetonide, medrysone, amcinafel, amcinafide,betamethasone and its other esters, chloroprednisone, clorcortelone,descinolone, desonide, dichlorisone, difluprednate, flucloronide,flumethasone, flunisolide, flucortolone, fluoromethalone, flup ero lone,fluprednisolone, meprednisone, methylmeprednisolone, paramethasone,cortisone acetate, hydrocortisone cyclopentylpropionate, cortodoxone,flucetonide, fludrocortisone acetate, flurandrenolone, aincinafal,amcinafide, betamethasone, betamethasone benzoate, chloroprednisoneacetate, clocortolone acetate, descinolone acetonide, desoximetasone,dichlorisone acetate, difluprednate, flucloronide, flumethasonepivalate, flunisolide acetate, fluperolone acetate, fluprednisolonevalerate, paramethasone acetate, prednisolamate, prednival,triamcinolone hexacetonide, cortivazol, formocortal and nivazol;

Pituitary hormones and their active derivatives or analogs such ascorticotrophin, thyrotropin, follicle stimulating hormone (FSH),luteinising hormone (LH) and gonadotrophin releasing hormone (GnRH);

Hypoglycemic agents such as insulin, chlorpropamide, glibenclamide,gliclazide, glipizide, tolazamide, tolbutamide and metformin;

Thyroid hormones such as calcitonin, thyroxine and liothyronine andantithyroid agents such as carbimazole and propylthiouracil;

Other miscellaneous hormone agents such as octreotide;

Pituitary inhibitors such as bromocriptine;

Ovulation inducers such as clomiphene;

Diuretics such as the thiazides, related diuretics and loop diuretics,bendrofluazide, chlorothiazide, chlorthalidone, dopamine,cyclopenthiazide, hydrochlorothiazide, indapamide, mefruside,methycholthiazide, metolazone, quinethazone, bumetanide, ethacrynic acidand frusemide and potasium sparing diuretics, spironolactone, amilorideand triamterene;

Antidiuretics such as desmopressin, lypressin and vasopressin includingtheir active derivatives or analogs;

Obstetric drugs including agents acting on the uterus such asergometrine, oxytocin and gemeprost;

Prostaglandins such as alprostadil (PGE1), prostacyclin (PGI2),dinoprost (prostaglandin F2-alpha) and misoprostol;

Antimicrobials including the cephalosporins such as cephalexin,cefoxytin and cephalothin;

Penicillins such as amoxycillin, amoxycillin with clavulanic acid,ampicillin, bacampicillin, benzathine penicillin, benzylpenicillin,carbenicillin, cloxacillin, methicillin, phenethicillin,phenoxymethylpenicillin, flucloxacillin, meziocillin, piperacillin,ticarcillin and azlocillin;

Tetracyclines such as minocycline, chlortetracycline, tetracycline,demeclocycline, doxycycline, methacycline and oxytetracycline and othertetracycline-type antibiotics;

Amnioglycoides such as amikacin, gentamicin, kanamycin, neomycin,netilmicin and tobramycin;

Antifungals such as amorolfine, isoconazole, clotrimazole, econazole,miconazole, nystatin, terbinafine, bifonazole, amphotericin,griseofulvin, ketoconazole, fluconazole and flucytosine, salicylic acid,fezatione, ticlatone, tolnaftate, triacetin, zinc, pyrithione and sodiumpyrithione;

Quinolones such as nalidixic acid, cinoxacin, ciprofloxacin, enoxacinand norfloxacin;

Sulphonamides such as phthalysulphthiazole, sulfadoxine, sulphadiazine,sulphamethizole and sulphamethoxazole;

Sulphones such as dapsone;

Other miscellaneous antibiotics such as chloramphenicol, clindamycin,erythromycin, erythromycin ethyl carbonate, erythromycin estolate,erythromycin glucepate, erythromycin ethylsuccinate, erythromycinlactobionate, roxithromycin, lincomycin, natamycin, nitrofurantoin,spectinomycin, vancomycin, aztreonam, colistin IV, metronidazole,tinidazole, fusidic acid, trimethoprim, and 2-thiopyridine N-oxide;halogen compounds, particularly iodine and iodine compounds such asiodine-PVP complex and diiodohydroxyquin, hexachlorophene;chlorhexidine; chloroamine compounds; and benzoylperoxide;

Antituberculosis drugs such as ethambutol, isoniazid, pyrazinamide,rifampicin and clofazimine;

Antimalarials such as primaquine, pyrimethamine, chloroquine,hydroxychloroquine, quinine, mefloquine and halofantrine;

Antiviral agents such as acyclovir and acyclovir prodrugs, famcyclovir,zidovudine, didanosine, stavudine, lamivudine, zalcitabine, saquinavir,indinavir, ritonavir, n-docosanol, tromantadine and idoxuridine;

Anthelmintics such as mebendazole, thiabendazole, niclosamide,praziquantel, pyrantel embonate and diethylcarbamazine;

Cytotoxic agents such as plicamycin, cyclophosphamide, dacarbazine,fluorouracil and its prodrugs (described, for example, in InternationalJournal of Pharmaceutics, 111, 223-233 (1994)), methotrexate,procarbazine, 6-mercaptopurine and mucophenolic acid;

Anorectic and weight reducing agents including dexfenfluramine,fenfluramine, diethylpropion, mazindol and phentermine;

Agents used in hypercalcaemia such as calcitriol, dihydrotachysterol andtheir active derivatives or analogs;

Antitussives such as ethylmorphine, dextromethorphan and pholcodine;

Expectorants such as carbolcysteine, bromhexine, emetine, quanifesin,ipecacuanha and saponins;

Decongestants such as phenylephrine, phenylpropanolamine andpseudoephedrine;

Bronchospasm relaxants such as ephedrine, fenoterol, orciprenaline,rimiterol, salbutamol, sodium cromoglycate, cromoglycic acid and itsprodrugs (described, for example, in International Journal ofPharmaceutics 7, 63-75 (1980)), terbutaline, ipratropium bromide,salmeterol and theophylline and theophylline derivatives;

Antihistamines such as meclozine, cyclizine, chlorcyclizine,hydroxyzine, brompheniramine, chlorpheniramine, clemastine,cyproheptadine, dexchlorpheniramine, diphenhydramine, diphenylamine,doxylamine, mebhydrolin, pheniramine, tripolidine, azatadine,diphenylpyraline, methdilazine, terfenadine, astemizole, loratidine andcetirizine;

Local anaesthetics such as benzocaine, bupivacaine, amethocaine,lignocaine, lidocaine, cocaine, cinchocaine, dibucaine, mepivacaine,prilocalne, etidocaine, veratridine (specific c-fiber blocker) andprocaine;

Stratum corneum lipids, such as ceramides, cholesterol and free fattyacids, for improved skin barrier repair [Man, et al. J. Invest.Dermatol., 106(5), 1096, (1996)];

Neuromuscular blocking agents such as suxamethonium, alcuronium,pancuronium, atracurium, curarie, gallamine, tubocurarine andvecuronium;

Smoking cessation agents such as nicotine, bupropion and ibogaine;

Insecticides and other pesticides which are suitable for localapplication;

Dermatological agents, such as vitamins A, C, B1, B2, B6, B12,B12.alpha. , and E, vitamin E acetate and vitamin E sorbate;

Allergens for desensitisation such as house, dust or mite allergens;

Nutritional agents and neutraceuticals, such as vitamins, essentialamino acids and fats;

Macromolecular pharmacologically active agents such as proteins,enzymes, peptides, polysaccharides (such as cellulose, amylose, dextran,chitin), nucleic acids, cells, tissues, and the like;

Bone and/or tissue mending biochemicals such as calcium carbonate,calcium phosphate, hydroxyapetite or bone morphogenic protein (BMP);

Angiogenic growth factors such as Vascular Endothelial Growth Factor(VEGF) and epidermal growth factor (EFG), cytokines interleukins,fibroblasts and cytotaxic chemicals; and

Keratolytics such as the alpha-hydroxy acids, glycolic acid andsalicylic acid; and

DNA, RNA or other oligonucleotides.

Additionally, the coacervates and biomaterials of the present inventionare particularly advantageous for the encapsulation, incorporationand/or scaffolding of macromolecular pharmacologically active agentssuch as pharmacologically active proteins, enzymes, peptides,polysaccharides, nucleic acids, cells, tissues, and the like. It isnoted that the encapsulation of certain pharmacologically active agentswith the biocoacervate or biomaterial of the present invention reduces,if not prevents, the potential for undesirable reaction with bodilyfluids or tissues that may otherwise occur upon implantation of areactive drug delivery device without protective encapsulation.Immobilization of macromolecular pharmacologically active agents into oronto biomaterials can be difficult due to the ease with which some ofthese macromolecular agents denature when exposed to organic solvents,some constituents present in bodily fluids or to temperaturesappreciably higher than room temperature. However, since the method ofthe present invention utilizes biocompatible solvents such as water,DMSO or ethanol the risk of the denaturation of these types of materialsis reduced. Furthermore, due to the size of these macromolecularpharmacologically active agents, these agents may be encapsulated withinthe coacervates or biomaterials of the present invention and thereby areprotected from constituents of bodily fluids that would otherwisedenature them. Thus, the coacervates and biomaterials of the presentinvention allow these macromolecular agents to exert their therapeuticeffects, while yet protecting them from denaturation or other structuraldegradation. Also, embodiments of the present invention includecoacervates or biomaterials that provide presentation of therapeuticmoieties of attached compounds to the biological surroundings.

Examples of cells which can be utilized as the pharmacologically activeagent in the coacervates, biomaterials and related devices of thepresent invention include primary cultures as well as established celllines, including transformed cells. Examples of these include, but arenot limited to pancreatic islet cells, human foreskin fibroblasts,Chinese hamster ovary cells, beta cell insulomas, lymphoblastic leukemiacells, mouse 3T3 fibroblasts, dopamine secreting ventral mesencephaloncells, neuroblastoid cells, adrenal medulla cells, endothelial cells,epithelial cells, hepatocytes, T-cells, combinations of these, and thelike. As can be seen from this partial list, cells of all types,including dermal, neural, blood, organ, stem, muscle, glandular,reproductive and immune system cells, as well as cells of all species oforigin, can be encapsulated and/or attached successfully by this method.

Examples of pharmacologically active proteins which can be incorporatedinto the coacervates or biomaterials of the present invention include,but are not limited to, hemoglobin, bone morphogenic protein,desmopressin, vasporessin, oxytocin, adrenocorticocotrophic hormone,epidermal growth factor, prolactin, luliberin or luteinising hormonereleasing factor, human growth factor, and the like; enzymes such asadenosine deaminase, superoxide dismutase, xanthine oxidase, and thelike; enzyme systems; blood clotting factors; clot inhibitors or clotdissolving agents such as streptokinase and tissue plasminogenactivator; antigens for immunization; hormones; polysaccharides such asheparin; oligonucleotides; bacteria and other microbial microorganismsincluding viruses; monoclonal antibodies, such as herceptin andrituximab; vitamins; cofactors; growth factors; retroviruses for genetherapy, combinations of these and the like.

An efficacious amount of the aforementioned pharmacologically activeagent(s) can easily be determined by those of ordinary skill in the arttaking into consideration such parameters as the particularpharmacologically active agent chosen, the size and weight of thepatient, the desired therapeutic effect, the pharmacokinetics of thechosen pharmacologically active agent, and the like, as well as byreference to well known resources such as Physicians'Desk Reference®:PDR—52 ed (1998)—Medical Economics 1974. In consideration of theseparameters, it has been found that a wide range exists in the amount ofthe pharmacologically active agent(s) capable of being incorporated intoand subsequently released from or alternatively allowed to exert theagent's therapeutic effects from within the coacervates or biomaterials.More specifically, the amount of pharmacologically active agent that maybe incorporated into and then either released from or active from withinthe coacervates or biomaterials may range from about 0.001% to about60%, more preferably, from about 0.05% to about 40%, most preferablyfrom about 0.1% to 20%, based on the weight of the coacervate materialor biomaterial. It is important to note that the pharmacologicallyactive agents are generally homogenously distributed throughout thecoacervate material or biomaterial thereby allowing for a controlledrelease of these agents.

Finally, one or more additive materials may be added to the coacervateor biomaterial to manipulate the material properties and thereby addadditional structure, enhance absorbance of the pharmacologically activeagents, enhance membrane permeation by pharmacologically active agents(cell and tissue), enhance mucoadhesion or modify the release ofpharmacologically active agents. That is, while a coacervate material orbiomaterial that includes a relatively fast-degrading protein materialwithout a particular additive material may readily degrade therebyreleasing drug relatively quickly upon insertion or implantation, acoacervate material or biomaterial that includes a particular polymericmaterial, such as polyanhydride, will degrade slowly, as well as releasethe pharmacologically active agent(s) over a longer period of time.Examples of biodegradable and/or biocompatible additive materialssuitable for use in the coacervate or biomaterial of the presentinvention include, but are not limited to polyurethanes, vinylhomopolymers and copolymers, acrylate homopolymers and copolymers,polyethers, cellulosics, epoxies, polyesters, acrylics, nylons,silicones, polyanhydride, poly(ethylene terephthalate), polyacetal,poly(lactic acid), poly(ethylene oxide)/poly(butylene terephthalate)copolymer, polycarbonate, poly(tetrafluoroethylene) (PTFE),polycaprolactone, polyethylene oxide, polyethylene glycol, poly(vinylchloride), polylactic acid, polyglycolic acid, polypropylene oxide,poly(alkylene)glycol, polyoxyethylene, sebacic acid, polyvinyl alcohol(PVA), 2-hydroxyethyl methacrylate (HEMA), polymethyl methacrylate,1,3-bis(carboxyphenoxy)propane, lipids, phosphatidylcholine,triglycerides, polyhydroxybutyrate (PHB), polyhydroxyvalerate (PHV),poly(ethylene oxide) (PEO), poly ortho esters, poly (amino acids),polycynoacrylates, polyphophazenes, polysulfone, polyamine, poly (amidoamines), fibrin, glycosaminoglycans such as hyaluronic acid orchondroitin sulfate, bioceramic materials such as hydroxyapetite,graphite, flexible fluoropolymer, isobutyl-based, isopropyl styrene,vinyl pyrrolidone, cellulose acetate dibutyrate, silicone rubber,copolymers of these, and the like.

Additionally, hydrophobic additives such as lipids can be incorporatedinto the coacervates or biomaterials to extend the duration of drugrelease or facilitate the incorporation of hydrophobic drugs. Exemplaryhydrophobic substances include lipids, e.g., tristearin, ethyl stearate,phosphotidycholine, polyethylene glycol (PEG); fatty acids, e.g.,sebacic acid erucic acid; combinations of these and the like. Aparticularly preferred hydrophobic additive useful to extend the releaseof the pharmacologically active agents comprises a combination of adimer of erucic acid and sebacic acid, wherein the ratio of the dimer oferucic acid to sebacic acid is 1:4.

Alternatively hydrophilic additives may be added to the coacervates orbiomaterials of the present invention to provide desirablecharacteristics, such as expedite delivery of the drugs or facilitatethe addition of other hydrophilic substances. Exemplary hydrophilicadditives useful to shorten the release duration of thepharmacologically active agent include but are not limited to, salts,such as sodium chloride; and amino acids, such as glutamine and glycine.

Other additive materials that may be incorporated into thebiocoacervates or biomaterials of the present invention to provideenhanced features include, but are not limited to, insoluble proteins(e.g. collagen, elastin . . . ), ceramics, bioceramics, glasses,bioglasses, glass-ceramics, resin cement, resin fill; more specifically,glass ionomer, calcium sulfate, Al₂O₃, tricalcium phosphate, calciumphosphate salts, sugars, lipoproteins, starches, ferrous salts andcompounds, carbohydrates, salts, polysaccharides, carbon, magneticparticles, fibers or other magnetic substances, humectants ormucoadhesive enhancers such as glycerol and alginate, absorption ormembrane permeation enhancers such as ascorbic acid, citric acid andLauroylcarnitine. Additional other materials that may be incorporatedinto the coatable composition include alloys such as, cobalt-based,galvanic-based, stainless steel-based, titanium-based, zirconium oxide,zirconia, aluminum-based, vanadium-based, molybdenum-based,nickel-based, iron-based, or zinc-based (zinc phosphate, zincpolycarboxylate).

Additionally other biocoacervate or biomaterial embodiments include abiocoacervate or biomaterial device that has incorporated into it amarker system that allows the device to be located and imaged usingultrasound, MRI, X-Ray, PET or other imaging techniques. The imagemarker can be made with air bubbles or density materials that allow easyvisualization of the device by ultrasound. The incorporated materialscan be metallic, gaseous or liquid in nature. Specific materials thatmay be utilized as image markers incorporated into the biocoacervate orbiomaterial devices include, but are not limited to, Gd-DPTA. It may bepossible to cause the biocoacervate or biomaterial to react to animaging technique, i.e., ultrasound to make bubbles or through theaddition of another chemical or substance to the system (e.g., peroxideaddition to a biocoacervate or biomaterial that contains peroxidase asan intrauterine marker that can be monitored by ultrasound). Also, theaddition of a harmless unique salt solution, or enzyme, may promote gasproduction by the biocoacervate or biomaterial as an ultrasound maker.The biocoacervate or biomaterial of the present invention can containagents that can be seen by ultrasound, MRI, PET, x-ray or any imagingdevice that is either known, in development or developed in the future.

The additives may be added at any time during the preparation of thecoacervate or biomaterial. For example additives, such as particles orfibers (drugs, insoluble proteins, hydroxy apetite . . . ),macromolecules (DNA, proteins, peptides, glycosaminoglycans (e.g.hyaluronic acid, chondroiten sulfate) . . . ), small molecules (NSAIDS,Sufentanil, Sirolimis, Paclitaxel, Estradiol, Capsaicin . . . ),combininations thereof and the like may be added to the protein solutionor may be added to the molten coacervate. Such addition has the benefitof distributing the additive homogeneously throughout the coacervate orbiomaterial.

If additives are to be incorporated into the coacervates or biomaterialsof the present invention, they will preferably be included in an amountso that the desired result of the additive is exhibited. Generally, ifincluded in embodiments of the biocoacervate of the present invention,the amount of additives may vary between from about 0.001% to about 60%,preferably from about 0.05% to 30% by weight, and most preferably fromabout 0.1% to 10% by weight based upon the weight of the biocoacervateor biomaterial.

One method of producing the coacervate of the present invention is byproviding one or more selected soluble or solubilized primary proteins,such as collagen, laminin or fibronectin and, in various embodiments,one or more soluble or solubilized secondary proteins such as elastin oralbumen. The primary and secondary proteins are added to a sufficientamount of biocompatible solvent, preferably water, under heat until theproteins are substantially dissolved in the solvent. The proteins areadded to the solvent that is generally heated to approximately 30-150°C., preferably 40-90° C., and most preferably 40-70° C. therebyproducing a protein solution. Once the protein solution is formed, oneor more glycosaminoglycans, such as heparin or chondroitin sulfate areadded to the protein solution thereby forming an amorphous coacervate,which drops out of the solution. It is noted that before adding the oneor more glycosaminoglycans to the protein solution one or more othermaterials (pharmacologically active agents, additives, etc.) may beadded to the one or more heated solvents (water) while stirring. It isalso noted that the secondary proteins may dissolve in a solutionseparate from the primary protein (e.g. the same solution as theglycosaminoglycan) and added to the primary protein solution prior to orwith the solution including the glycasaminoglycan. Once the coacervatehas dropped out of solution, the solution and coacervate are normallyallowed to cool to between 0-35° C., preferably 10-25° C., mostpreferably 17-22° C. and the solution is poured off the coacerate or thecoacervate is extracted from the solution.

Many embodiments of the biocoacervate and biomaterials of the presentinvention are thermoplastics, thereby possessing thermoplastic chemicaland mechanical characteristics. Therefore, the biocoacervates and someembodiments of the biomaterials have the property of softening whenheated and of hardening again when cooled; these thermoplastic materialscan be remelted and cooled time after time without undergoing anysubstantial chemical change. In view of these thermoplasticcharacteristics, various embodiments of the formed biocoacervate may bereformed into any shape and size by simply heating the biocoacervateuntil it melts and forms a liquid. The melted biocoacervate may also beutilized to coat devices or materials. Generally, the biocoacervate canbe melted at a temperature between 20-120° C., preferably 25-80° C.,most preferably 30-65° C. Next, the melted biocoacervate may be pouredinto a cast or mold or spray or dip coated onto a device or material andallowed to cool, thereby resolidifying and reforming into the desiredshape and/or size. FIG. 3 depicts an example of the biocoacervate of thepresent invention formed into a square shape. It is noted that at highlevels of crosslinking the thermoplastic characteristics of some of theembodiments of the present invention may diminish.

It is noted that in forming the protein solution, the primary andsecondary proteins, the biocompatible solvent(s), and optionally thepharmacologically active agent(s) and additive(s) may be combined in anymanner. For example, these components may simply be combined in onestep, or alternatively, the primary and secondary protein materials maybe dissolved in one or multiple biocompatible solvents and an additionalprotein material, pharmacologically active agent and/or additive may bedissolved and/or suspended in the same or another biocompatible solvent.Once the components are placed into one or more solutions, the resultingsolutions may be mixed to precipitate the amorphous biocoacervate.

Once the coacervate is formed, it may be optionally pressed or vacuumedto further form, modify, set the configuration and/or remove any excesssolvent or air trapped within the biocoacervate. It is noted that theresulting coacervate may be melted and placed in vacuum to remove anyexcess air trapped within the coacervate. The pressing may also beperformed when a melted coacervate is resetting to a solid state bypouring the melted coacervate in a mold and applying pressure whilecooling. The biocoacervate may optionally be dried to reduce watercontent to transform the coacervate gel-like structure into more of acohesive body material to allow it to accept compression. Any manuallyor automatically operable mechanical, pneumatic, hydraulic, orelectrical molding device capable of subjecting the coacervate topressure is suitable for use in the method of the present invention. Inthe production of various embodiments of the present invention, amolding device may be utilized that is capable of applying a pressure offrom about 100 pounds per square inch (psi) to about 100,000 psi for atime period of about one (1) seconds to about forty-eight (48) hours.Preferably, the molding device used in the method of the presentinvention will be capable of applying a pressure of from about 1000 psito about 30,000 psi for a time period of from about two (2) seconds toabout sixty (60) minutes. More preferably, the molding device used inthe method of the present invention will be capable of applying apressure of from about 3,000 psi to about 25,000 psi for a time periodof from about three (3) seconds to about ten (10) minutes.

Compression molding devices suitable for use in the practice of themethod of the present invention are generally known. Suitable devicesmay be manufactured by a number of vendors according to providedspecifications, such as desirable pressure, desired materials forformulation, desired pressure source, desired size of the moldable andresulting molded device, and the like. For example, Gami Engineering,located in Mississauga, Ontario manufactures compression molding devicesto specifications provided by the customer. Additionally, manycompression molding devices are commercially available. See U.S. Pat.No. 6,342,250 and U.S. application Ser. No. 09/796,170, which areincorporated by reference herein, for a description of one type ofcompression molding device that may be utilized in the process of thepresent invention.

As previously indicated, the biocoacervate of the present invention isnot soluble in water at room temperature. However, the coacervate doesdissolve in saline solution or other physiological solutions. Abiocoacervate or biomaterial that does not dissolve in saline solutionor other physiological solutions may be produced by setting thebiocoacervate in the desired configuration and size by utilizing acrosslinking technique. It is also noted that various crosslinkingreagents, techniques and degrees of crosslinking manipulate the meltingpoint of the crosslinked material and its physical and biologicalcharacteristics. It has been found that the application of crosslinkingto the biocoacervate will generally tend to raise the melting point ofthe biocoacervate.

Many crosslinking techniques known in the art may be utilized to set thebiocoacervate into the desired configuration, thereby forming abiomaterial that does not dissolve in saline solution. For example,embodiments of the biocoacervate may be crosslinked by reacting thecomponents of the biocoacervate with a suitable and biocompatiblecrosslinking agent. Crosslinking agents include, but are not limited toglutaraldehyde, p-Azidobenzolyl Hydazide,N-5-Azido-2-nitrobenzoyloxysuccinimide,4-[p-Azidosalicylamido]butylamine, glycidyl ethers such as 1,4-butandioldiglycidylether, any other suitable crosslinking agent and anycombination thereof. A description and list of various crosslinkingagents and a disclosure of methods of performing crosslinking steps withsuch agents may be found in the Pierce Endogen 2001-2002 or 2003-2004Catalog which is hereby incorporated by reference. It is also noted thatmultiple applications of crosslinking agents at different stages mayproduce desired products. For example, crosslinking the biocoacervateafter initial formation and then again following particle formation ofthe biocoacervate has proven effective.

Furthermore, it is noted that embodiments of the coacervates of thepresent invention may include crosslinking reagents that may beinitiated and thereby perform the crosslinking process by UV lightactivation or other radiation source, such as ultrasound or gamma ray orany other activation means.

The protein biocoacervate may also be crosslinked by utilizing othermethods generally known in the art. For example, the coacervates of thepresent invention may be partially or entirely crosslinked by exposing,contacting and/or incubating a coacervate with a gaseous crosslinkingreagent, liquid crosslinking reagent, light, heat or combinationthereof. In various embodiments of the present invention the coacervatemay be crosslinked by contacting the coacervate with a liquidcrosslinking reagent, such as glutaraldehyde or 1,4-butandioldiglycidylether. In one preferred embodiment of the present inventionthe coacervate is crosslinked in a solution of between 0.01%-50%gluteraldehyde. Additionally, it is noted that in processes including acrosslinking agent the coacervate is generally exposed to thecrosslinking agent for a period of 1 min to 24 hours, preferably between5 min. and 6 hours and more preferably between 15 min. and 3 hours.

Embodiments of the present invention may also include the addition ofreagents to properly pH the resulting coacervate, biomaterial andrelated devices of the present invention. These pH reagents may be addedto the coacervate during formation of the coacervate, exposing theformed coacervate to a solution of the desired pH or adjusting the pHwhen the coacervate is in a melted state. The appropriate adjustment ofpH thereby enhances the biocompatible characteristics of thebiomaterials with the host tissue of which it is to be administered andmay also act to stabilize the material in physiologic conditions. Whenpreparing the coacervate, the pH reagents are generally added to theprotein solution prior to addition of the glycosaminoglycans. However,the pH reagent may alternatively be added after the amorphous coacervateis formed. For example the pH reagent may be added to the melted form ofthe coacervate in the attempt to obtain the proper pH levels. In variousembodiments of the present invention, the adjustment of pH can beperformed by the addition of drops of 0.05N to 4.0N acid or base to theprotein solution or melted coacervate until the desired pH is reached asindicated by a pH meter, pH paper or any pH indicator. More preferably,the addition of drops of 0.1N-0.5N acid or base are used. Although anyacid or base may be used, the preferable acids and bases are HCl andKOH, NaOH or combinations thereof, respectively. It has been found thatadjusting the pH at or between 4 and 9, and in many embodiments at orbetween 6 and 8, have provided beneficial materials.

The resulting biocoacervate preferably has the maximum solvent amountabsorbable with as little excess solvent as possible while still beingstructured into a shape-holding amorphous solid and possessing thedesired features relevant to the material's and/or device's function,e.g., preferably a solvent content of from about 20% to about 90%, morepreferably a solvent content of from about 30% to about 80% and mostpreferably 40% to 75%. Additionally, the amount of proteins andglycosaminoglycan found in the resulting coacervate or biomaterial mayvary between from about 10% to about 80%, in some embodiments from about20% to 70% by weight, and in other embodiments from about 25% to 60% byweight based upon the weight of the resulting biocoacervate orbiomaterial. The amount of glycosaminoglycan present in variousembodiments of the present invention generally is about 3% to about 25%,in some embodiments about 5% to 20% by weight, and in other embodimentsabout 8% to 15% by weight based upon the weight of the protein includedin the biocoacervate.

Since biocompatible proteins and solvents are used in the manufacture ofthe biocoacervates, biomaterials and related devices of the presentinvention, the potential for adverse tissue reactions to foreignsubstances, such as chemical solvents are reduced, if not substantiallyprecluded. For all of these reasons, the coacervates and biomaterials inaccordance with the present invention may advantageously be used toeffect a local therapeutic result in a patient in need of suchtreatment. More specifically, the biocoacervates and biomaterials of thepresent invention may be injected, implanted, or administered via oral,sublingual, mucosal, as well as nasal, pulmonary, subcutaneous,intradermal or any parenteral modes of delivery. Moreover, thecoacervates or biomaterials may be delivered to a site within a patientto illicit a therapeutic effect either locally or systemically. Forexample, depending on the desired therapeutic effect, the coacervates orbiomaterials may be used to regenerate tissue, repair tissue, replacetissue, and deliver local and systemic therapeutic effects such asanalgesia or anesthesia, or alternatively, may be used to treat specificconditions, such as coronary artery disease, heart valve failure, corneatrauma, neural tissue defects or trauma, skin wounds, burned skin, bonedefects and trauma, ligament defects and trauma, cartilage defects andtrauma wrinkles and other tissue specific conditions. The coacervates orbiomaterials that include pharmacologically active agents may beutilized in instances where long term, sustained, controlled release ofpharmacologically active agents is desirable, such as in the treatmentof surgical and post-operative pain, cancer pain, or other conditionsrequiring chronic pain management.

The patient to which the coacervates or biomaterials are administeredmay be any patient in need of a therapeutic treatment. Preferably, thepatient is a mammal, reptile or bird. More preferably, the patient is ahuman. Furthermore, the coacervates or biomaterials can be implanted inany location to which it is desired to effect a local therapeuticresponse. For example, the coacervates, biomaterials or related devicesmay be administered, applied, sutured, clipped, stapled, gas delivered,injected and/or implanted vaginally, in ova, in utero, in uteral,subcutaneously, near heart valves, in periodontal pockets, in the eye,in the intracranial space, next to an injured nerve, next to the spinalcord, intradermally etc. Furthermore, implanted coacervates,biomaterials or related devices may absorb water and swell, therebyassisting the coacervates, biomaterials or related devices to staysubstantially in the location where it was implanted or injected.

The present invention will now be further described with reference tothe following non-limiting examples and the following materials andmethods were employed. It is noted that any additional featurespresented in other embodiments described herein may be incorporated intothe various embodiments being described.

Drug Delivery Devices and Tissue Fillers:

As previously suggested, various embodiments of the biocoacervates andbiomaterials of the present invention may be utilized as drug deliverydevices or tissue fillers. A drug delivery device or tissue fillerproduced and administered as previously disclosed or suggested includesthe biocompatible features of the components of the biocoacervate orbiomaterial and thereby reduces or prevents the undesirable effects oftoxicity and adverse tissue reactions that may be found in many othertypes of drug delivery devices. Furthermore, the controlled releasecharacteristics of this type material provides for a higher amount ofpharmacologically active agent(s) that may be incorporated into thebiocoacervate or biomaterial. The controlled release ofpharmacologically active agent, if present, is partially attributed tothe homogenous distribution of the pharmacologically active agent(s)throughout the biocoacervate or biomaterial. This homogenousdistribution provides for a more systematic, sustainable and consistentrelease of the pharmacologically active agent(s) by gradual degradationof the coacervate or material or by diffusion of the pharmacologicallyactive agent(s) out of the coacervate or material. As a result, therelease characteristics of the pharmacologically active agent from thebiocoacervate, biomaterial and/or device are enhanced.

Additionally, as previously mentioned, other optional biocompatibleadditives, if included in the coacervate or biomaterial, will becompelled and influenced to interact with the various components,including the pharmacologically active agents if present, to augmenttheir biodurability, biocompatibility and/or drug releasecharacteristics if drugs are present in the materials. Augmentation mayinclude inhibiting or enhancing the release characteristics of thepharmacologically active agent(s), if present. For example, amulti-layered drug delivery device may comprise alternating layers ofbiocoacervates or biomaterials that have sequential inhibiting andenhancing biocompatible additives included, thereby providing a pulsingrelease of pharmacologically active agents. A specific example may beutilizing glutamine in a layer as an enhancer and polyanhydride as aninhibitor. The inhibiting layer may include drugs or no drugs.

The drug delivery devices or tissue fillers of present invention may beformed into any shape and size, such as a cylinder, a tube, a wafer,particles or any other shape that may optimize the delivery of thedevices or fillers and optionally the incorporated pharmacologicallyactive agents included therein. For example, the composite coacervate orbiomaterial may be processed into particles for subsequent administationas a therapeutic device such as a tissue filler or drug delivery device.

An illustration of an embodiment of the particles of the presentinvention is depicted in FIG. 4A. In one embodiment of the presentinvention the particles are produced utilizing the biocoacervate orbiomaterial of the present invention as previously described. Methods ofproducing the particles utilized in products of the present inventionincludes crushing, cutting, pulverizing, homogenizing or grinding of thebiocoacervate or biomaterial in either wet or dry conditions until theparticles are formed. The particle formation process may be performedwith the biocoacervate or biomaterial in its original state or afterapplying heat, freeze drying techniques such as liquid nitrogen freezedrying or dry ice freeze drying, vacuum or other similar dryingtechniques to eliminate excess solvent from the biocoacervate orbiomaterial. Various particle embodiments of the present invention aresubstantially insoluble thereby allowing them to be integrated andremodeled by the host tissue rather than be consumed and excreted. FIG.4B depicts a single particle of one embodiment of the biocoacervate ofthe present invention illustrated using frozen sample scanning electronmicroscopy.

One example of an alternative method to make particles is byhomogenizing a crosslinked coacervate thereby producing particles. Insuch a method a block or other shape of the coacervate may becrosslinked with a crosslinking agent, such as 0.01M to 10Mgluteraldehyde or 1,4-butandiol diglycidylether. Once crosslinked thebiocoacervate is next placed in a homgenizer and cut into particles. Oneor more additional crosslinking steps may be performed afterhomogenization of the coacervate by exposing the particles to a secondsolution including one or more crosslinking agents, such asgluteraldehye, formaldehyde, glyoxal or 1,4-butandiol diglycidylether.It is noted that alternative crosslinking solutions and conditions (e.g.pH, temperature, solvents . . . ) may be utilized for the extracrosslinking steps.

Generally, the particles may vary in size but are normally approximately10 nm-5 mm, preferably 500 nm-2.5 mm and more preferably 1-1000 μm.*** Acharacteristic of the particles produced from the biocoacervate materialis that they no longer aggregate when in the particulate state.Furthermore, prior studies have demonstrated that the particles do notaggregate in saline and are easily delivered through small gaugeneedles, such as 27 or 30 guage needles. The particles can be made todisassociate at very slow or fast rates in aqueous solutions.

After the particles are formed using the various methods describedabove, they are characterized for their basic structure. First theparticles may be segregated using a series of pharmaceutical drugsieves.

In various embodiments of the present invention, the particles may beutilized as a drug delivery device or a tissue filler by administeringthem subcutaneously or intradermally to the patient by a variety ofadministration techniques known in the art. One such administrationprocedure of the present invention comprises a syringe injection of suchparticles or a slurry of such particles into the desired site. Saline isa solution that may be employed to prepare such a slurry, but anybiocompatible solution may be utilized. Also, lubricants, such aspolyvinylalcohol, polyethylene glycol, dextran, proteins (human, bovine,porcine, or equine) such as collagen, elastin, albumin, proteoglycans orglycans, hyaluronic acid, lipids, oils or any other lubricious agent,may be added to the particles or slurry to facilitate injection of theparticles through a needle syringe assembly. These lubricants assist infacilitating the administration of the particles through the applicator,such as a syringe and also may be made to act as an immunogenic mask,thereby reducing potential inflammatory and/or immune responses. Invarious embodiments of the present invention the lubricants may compriseapproximately less than 5% and preferably less than 1% of the particleor slurry contents. Saline has been selected for the initial materialfor several reasons including its common use in medical procedures andits availability in a sterile form.

The particles or particle slurry may be delivered in any way known inthe art including delivery through a needle, air-gun, iontophoresis,spray bottle, etc. Any gauge needle may be utilized to deliver theslurry containing the particles of the present invention, including butnot limited to 12-30 gauge needles. FIG. 5 depicts one embodiment of theparticles of the present invention wherein a slurry of particles andsaline are delivered through a 27 guage needle. It is noted again thatthe particles may optionally include one or more pharmacologicallyactive agents. However, a suitable tissue filler may comprise a proteincoacervate material without the presence of pharmacologically activeagents.

Alternatively, the particles of the present invention may also be placedinto position without utilizing needles, such as when the particles aretoo large to fit through a needle. These particles are typically 0.5-5mm in size, more typically 1-25 mm. In such a procedure the particlesmay be surgically implanted and packed into and/or around the injuredsite. For example, particles may be surgically packed into and around aninjured or vacant area and subsequently sealed into position by the hosttissue surrounding the injured area, such as a fractured bone. Theinjection or implantation of biocompatible particles of the presentinvention allows for the particles to remodel with and/or resorb intothe surrounding tissue or remain positioned in the injured or vacantarea after it has mended or healed.

Also, various embodiments of particles of the present invention may beadministered as a drug delivery device orally or through the mucosaltissue. For example a particle loaded saline solution may beadministered as a nasal spray to deliver one or more pharmacologicallyactive agents. The spray may be similar to the slurry previouslydescribed, but may likely include a lower concentration of particles tosaline compared to the slurry prepared for injection. This type ofparticulate solution may be administered by any means known in the art,such as a nasal spray bottle or an inhaler.

Finally, additional embodiments of biocoacervate drug delivery devicesof the present invention includes the production of therapeutic devicesand/or medical device coatings utilizing the biocoacervate of thepresent invention. For example, the biocoacervate of the presentinvention may be formed into a drug delivery device or wound healingdevice in the form of a cylinder, wafer, particles, capsule forinclusion of drug or any other suitable shape or design. The shape ofthe delivery device may be formed by any device known in the art, suchas a conventional pill press, molds, casts or any of the molding orshaping devices known in the art. For example a drug delivery device orwound healing device comprising one or more proteins, such as collagen,keratin, laminin, fibronectin, silk, silk fibroin, actin, myosin,fibrinogen, thrombin, aprotinin, elastin and/or albumen, one or moreglycosaminoglycans such as heparin, one or more biocompatible solventssuch as water, DMSO, ethanol and/or glycerol and one or morepharmacologically active agents, such as ibuprofen, capsaicin, fentanyl,benzocaine, botox, acetaminophen or desmopressen may be produced. In oneexample, a delivery device can be adhered to the inside of the mouth ornose by simply applying or pressing the device, such as a wafer orparticles, to the mucosal tissue. The device will generally deliver thedrug through the mucosal tissue without losing drug orally.

Also, a release mechanism may be included in the biocoacervate orbiomaterial for the release of the one or more pharmacologically activeagents. The release mechanism may be a material that encapsulates alarger drug delivery device, such as a cylinder or the release mechanismmay be within the coacervate or biomaterial that includes encapsulatedparticles of either the drug delivery device or particles of one or morepharmacologically active agents. Additionally, the coacervate orbiomaterial of the present invention may also encapsulate a drugdelivery device larger and/or different than a particle that is coveredby the release mechanism material.

FIG. 6 depicts an embodiment of a drug delivery device that includes arelease mechanism. The release mechanism 40 is positioned within abiocoacervate or biomaterial 42. Generally, the mechanism 40 is amaterial that creates a shell around the pharmacologically active agents44 and inhibits their release until opened by some outside stimuli 46.Normally, the pharmacologically active agent can be released by a pulseof energy, radiation or a chemical reagent acting upon the encapsulatingsubstance. For example, a drug delivery device comprising apharmacologically active agent encapsulated in a polyanhydride coatinginhibits release of the pharmacologically active agent and/or itsinteraction with the host tissue. In this example, the pharmacologicallyactive agents can be released when the polyanhydride surface iscontacted with an energy pulse, such as an ultrasound pulse. Such anembodiment has many advantages in treating afflictions that may requirean extended time period before release of the pharmacologically activeagent is necessary.

Treatment of cancer or chronic pain may be examples of afflictions thatmay benefit from such an embodiment. The retention of chemotherapy drugslocalized in an area of the patient that includes cancerous tissue maybe beneficial to the long term treatment of the patient. The treatmentmay include implantation of a drug delivery device that includes arelease mechanism in a position of the body wherein cancerous tissueshas been previously resected. Upon determination that cancerous cellgrowth may be ongoing or occurring again, the drug delivery device canbe released by some stimuli, such as a ultrasound pulse or chemicalreagent. The stimuli opens the release mechanism material and allows thehost tissue to interact with the pharmacologically active agents.

Encapsulated or Coated Stents and Medical Devices:

Other embodiments of the present invention include the utilization ofthe biocoacervates or biomaterials to encapsulate or coat stents orother medical devices. A valuable attribute of such coatings is thehemocompatiblity of these biocoacervates and biomaterials. Thebiocoacervates or biomaterials of this invention can be used to coat thesurface of a variety of implantable devices, for example:drug-delivering vascular stents (e.g., self-expanding stents typicallymade from nitinol, balloon-expanded stents typically prepared fromstainless steel); other vascular devices (e.g., grafts, catheters,valves, artificial hearts, heart assist devices); implantabledefibrillators; blood oxygenator devices (e.g., tubing, membranes);surgical devices (e.g., sutures, staples, anastomosis devices, vertebraldisks, bone pins, suture anchors, hemostatic barriers, clamps, screws,plates, clips, vascular implants, tissue adhesives and sealants, tissuescaffolds); membranes; cell culture devices; chromatographic supportmaterials; biosensors; shunts for hydrocephalus; wound managementdevices; endoscopic devices; infection control devices; orthopedicdevices (e.g., for joint implants, fracture repairs); dental devices(e.g., dental implants, fracture repair devices), urological devices(e.g., penile, sphincter, urethral, bladder and renal devices, andcatheters); colostomy bag attachment devices; ophthalmic devices (e.g.intraocular coils/screws); glaucoma drain shunts; synthetic prostheses(e.g., breast); intraocular lenses; respiratory, peripheralcardiovascular, spinal, neurological, dental, ear/nose/throat (e.g., eardrainage tubes); renal devices; and dialysis (e.g., tubing, membranes,grafts), urinary catheters, intravenous catheters, small diametergrafts, vascular grafts, artificial lung catheters, atrial septal defectclosures, electro-stimulation leads for cardiac rhythm management (e.g.,pacer leads), glucose sensors (long-term and short-term), degradablecoronary stents (e.g., degradable, non-degradable, peripheral), bloodpressure and stent graft catheters, birth control devices, BHP andprostate cancer implants, bone repair/augmentation devices, breastimplants, cartilage repair devices, dental implants, implanted druginfusion tubes, intravitreal drug delivery devices, nerve regenerationconduits, oncological implants, electrostimulation leads, painmanagement implants, spinal/orthopedic repair devices, wound dressings,embolic protection filters, abdominal aortic aneurysm grafts, heartvalves (e.g., mechanical, polymeric, tissue, percutaneous, carbon,sewing cuff), valve annuloplasty devices, mitral valve repair devices,vascular intervention devices, left ventricle assist devices, neuroaneurysm treatment coils, neurological catheters, left atrial appendagefilters, hemodialysis devices, catheter cuff, anastomotic closures,vascular access catheters, cardiac sensors, uterine bleeding patches,urological catheters/stents/implants, in vitro diagnostics, aneurysmexclusion devices, and neuropatches.

Examples of other suitable devices include, but are not limited to, venacava filters, urinary dialators, endoscopic surgical tissue extractors,atherectomy catheters, clot extraction catheters, PTA catheters, PTCAcatheters, stylets (vascular and non-vascular), coronary guidewires,drug infusion catheters, esophageal stents, circulatory support systems,angiographic catheters, transition sheaths and dialators, coronary andperipheral guidewires, hemodialysis catheters, neurovascular ballooncatheters, tympanostomy vent tubes, cerebro-spinal fluid shunts,defibrillator leads, percutaneous closure devices, drainage tubes,thoracic cavity suction drainage catheters, electrophysiology catheters,stroke therapy catheters, abscess drainage catheters, biliary drainageproducts, dialysis catheters, central venous access catheters, andparental feeding catheters.

Other examples of medical devices suitable for the present inventioninclude, but are not limited to implantable vascular access ports, bloodstorage bags, blood tubing, central venous catheters, arterialcatheters, vascular grafts, intraaortic balloon pumps, cardiovascularsutures, total artificial hearts and ventricular assist pumps,extracorporeal devices such as blood oxygenators, blood filters,hemodialysis units, hemoperfusion units, plasmapheresis units, hybridartificial organs such as pancreas or liver and artificial lungs, aswell as filters adapted for deployment in a blood vessel in order totrap emboli (also known as “distal protection devices”).

A stent is a tube made of metal or plastic that is inserted into avessel or passage to keep the lumen open and prevent closure due to astricture or external compression. Stents are commonly used to keepblood vessels open in the coronary arteries, into the oesophagus forstrictures or cancer, the ureter to maintain drainage from the kidneys,or the bile duct for pancreatic cancer or cholangiocarcinoma. Stents arealso commonly utilized in other vascular and neural applications to keepblood vessels open and provide structural stability to the vessel.Stents are usually inserted under radiological guidance and can beinserted percutaneously. Stents are commonly made of gold, stainlesssteel, nitinol or cobalt chromium alloys. However, stents constructed ofany suitable material may be utilized with the coacervates orbiomaterials of the present invention.

Encapsulation or coating of a stent or other medical device with thecoacervates or biomaterials of the present invention produces a devicethat is more biocompatible with the host tissue than the stent alone.Such encapsulation or coating of the stent or other medical devicereduces or prevents adverse immuno-response reactions to the stentdevice being administered and further enhances acceptance and remodelingof the device by the host tissue. Furthermore, encapsulated or coatedstents or medical devices may also include one or more pharmacologicallyactive agents, within or attached to the coacervates or biomaterialsthat may assist in the facilitation of tissue acceptance and remodelingas well as inhibit additional adverse conditions sometimes related toimplantation. For example the release of certain pharmacologicallyactive agents from the biocoacervate or biomaterial coating on a stent,may prevent blockage of a blood vessel due to platelet aggregation, cellproliferation, inflammation or thrombosis. In addition to anti-plateletaggregation drugs, anti-inflammatory agents, gene altering agents suchas antisense, antiproliferative agents, angiogenesis inhibitors andother pharmacologically active agents can be administered locally to thehost tissue through the biocoacervate coating of the present invention.

The coacervates or biomaterials may completely encapsulate or otherwisecoat the exterior of the stent or other medical device. The stent ormedical device may be coated or encapsulated with the biocoacervate orbiomaterial of the present invention utilizing any coating orencapsulation process known in the art, such as dip coating, spraying,compression molding, casting etc. For example, a stent may be spraycoated with one or more embodiments of the present invention while in amelted state; the coating subsequently solidfies around the stent uponcooling. Also, the medical device or stent may be precoated with anadhesive enhancer, such as Parylene to enhance the adhesion of thebiocoacervate to the device. In various embodiments of the presentinvention, the stent or medical device is coated with a coacervate thatis subsequently set by utilizing one of the previously describedcrosslinking techniques. In other embodiments an elastic cover of thebiocoacervate or biomaterial may be made to fit over or encapsulate allor part of a medical device, such as pacemaker, valve, or catheter.

In one embodiment as depicted in FIG. 7, a compression molding devicewherein the inner insert 18 includes a mandrel 29 that extends upwardfrom the insert 18 into the chamber 17 is utilized to coat a stent 32.Following preparation of the coacervate 23, inner insert 18 is insertedinto the cavity 16. A stent 32 is positioned over the mandrel 29, thecoacervate 23 is melted and subsequently placed in the cavity. Once thestent 32 and coacervate 23 are placed in the cavity 16, they are pressedwhile cooling to form an encapsulated stent. Encapsulation or coating ofthe stent 32 is determined by the size of the mandrel 29 utilized in thecompression molding device. A stent 32 that fits snuggly over themandrel 29 will allow for only a coating upon the exterior of the stent32. A smaller mandrel 29 that does provide a snug fit for the stent 32will allow biocoacervate material to move between the mandrel 29 and thestent 32 thereby creating an encapsulation of the stent 32. Followingcompression, the encapsulated or coated stent device is then removedfrom the compression molding device and crosslinked to set thecoacervate and form a biomaterial coated stent. In various embodiments,the stent device, either encapsulated or coated, has a wall thickness ofapproximately 0.05 mm to 2 mm and preferably has a wall thickness of0.15 to 0.50 mm.

As previously described additional additives may be included in thecoacervates or biomaterials to provide additional structural stabilityand durability to the encapsulated or coated stent device. In twoembodiments, the stent device of the present invention may be producedby preparing a coated stent device that includes a ratio of 1:2:6heparin to elastin to collagen and 1:2:6 condroitin sulfate to elastinto collagen.

Furthermore, the coacervates and biomaterials used to coat stent devicescan also be used to incorporate peptides and other materials that havethe ability to inhibit cell migration. A disadvantage of utilizingstents in a vessel is that the expansion of the vessel upon insertion ofthe stent injures the vessel and may allow smooth muscle cells to enterinto the vessels thereby occluding or restenosing the vessel throughcellular proliferation. Occlusion of the vessel and restenosis can betreated by utilizing the coated stent device and vessels or tube graftsof the present invention. Vessels and tubular grafts will be explainedlater in the text of this disclosure. It is important to note thatinserting a stent coated with the coacervate or biomaterials of thepresent invention, with or without drugs, can prevent such breakdown andgrowth of cells into the diseased or damaged vessel.

Tissue Grafts:

Additional embodiments of the present invention include the utilizationof the biocoacervates and/or biomaterials in producing tissue graftssuch as vessels; tubular grafts such as tracheal tubes, bronchial tubes,catheter functioning tubes, lung, vertebral discs, gastrointestinalsegments; valves; cartilage; tendons; ligaments; skin; pancreaticimplant devices; breast implants; tissue fillers, such as void orwrinkle fillers, urinary or sphicter fillers to correct incontinence;other types of tissue that relate to the heart, brain, nerve, spinalcord, nasal, liver, muscle, bone, thyroid, adrenal, pancreas, andsurrounding tissue such as connective tissue, pericardium andperitoneum. It is noted that a tube does not necessarily have to becylindrical in shape, but is generally found in that configuration.

In various embodiments of the present invention the biocoacervate orbiomaterial may be coated or impregnated onto or into a scaffolding typestructure, such as a polyurethane foam tube, methacrylate meshing orfoam, nylon meshing, polypropylene/polytetrafluoroethylene mesh or meshtube, cotton knitted material, Dacron knitted material,polytetrafluoroethylene, silk and Teflon. FIG. 8 depicts an embodimentof a polypropylene/polytetrafluoroethylene mesh tube, such as thatproduced by Secant, Inc., before the biocoacervate material of thepresent invention is applied. In one embodiment of the presentinvention, as depicted in FIGS. 9A-B, apolypropylene/polytetrafluoroethylene mesh tube, as shown in FIG. 8, isprepared by applying the melted biocoacervate to the tube and supplyingvacuum to remove trapped air within the pores of the tube. It is notedthat in other embodiments of the present invention, the scaffoldingstructure of the vessel graft may be a cotton tube or a polyurethanefoam tube rather than the a polypropylene/polytetrafluoroethylene meshtube. Finally, FIG. 9C depicts the vessel graft including apolypropylene/polytetrafluoroethylene mesh tube that has been placedunder hydrostatic pressure of over 200 psi for greater than 3 days.

FIGS. 10A-B depict magnified cross-sectional views of one embodiment ofa vessel of the present invention wherein the interior layer of apolyurethane foam tube adjacent to the lumen is predominately comprisedof biocoacervate or biomaterial, the middle layer of the vessel includesan coacervate or biomaterial impregnated within a polyurethane foam andthe exterior layer of the vessel is comprised of biocoacervate orbiomaterial. FIG. 11A depicts another embodiment of a vessel graftimplanted in a pig wherein the structural scaffolding of the vesselgraft is a cotton knit material coated with another embodiment of acrosslinked biocoacervate material of the present invention. FIG. 11B isthe angiogram image of the same vessel depicted in FIG. 11A after beingimplanted for nine days showing that the vessel graft remains patent.Histology showed after thirty days that the blood vessel graft did notclot blood and did not allow platelet attachment or any thrombosis. Itwas also found that smooth muscle cells and microvasculature wereremodeling the crosslinked biocoacervated material.

The melted biocoacervate may be applied to the scaffolding structure,such as a polyurethane or cotton knit tube, by any process known in theart such as painting, injection molding, dip coating, spraying and thelike. Furthermore, a scaffolding tubular structure may be strengthenedby applying one or more rings of biocompatible polymer, such as Dacronto prevent tearing or crimping of the tubular graft ends. Alternatively,any materials including those identified above may be coated with thebiocoacervate of the present invention utilizing the same process asdescribed in the previous few sentences.

In view of such scaffolding structures, vessels and tubular grafts maybe synthesized utilizing the biocoacervate and/or biomaterial.Generally, a vessel is a tubular graft made of the coacervates orbiomaterials that can support the growth of cells on and/or within thecoacervate or biomaterial. For example, vessels may be producedutilizing the coacervates or biomaterials that have the affinity tosupport growth of endothelial cells on the inside of the tube and smoothmuscle cells on the outside of the tube. Furthermore, tubular graftsincluding such biocoacervates and biomaterials tend to have beneficialhemocompatible characteristics. FIG. 12A-B depicts various embodimentsof tubes made of the biomaterial of the present invention whereinendothelial cells are present on the surface of the biomaterial.Alternatively, a multi-layered vessel may be created with two or moreseparate tubes, wherein a smaller tube with endothelial cells grown onthe inside of the tube is inserted into a larger tube with smooth musclecells grown on the outside of the tube. Additional tubular layers may beincluded in the vessel that may or may not include the growth of cellson the surfaces or within the coacervates or biomaterials. The layersmay also contain pharmacologically active agents and/or more structuralcomponents, such as polymeric materials, knitted materials or stents.The layers will generally stay in position through adhesives, fastenerslike sutures, melted biocoacervate solvent welding, cell interaction,pressure fitting, crosslinking, intermolecular forces and other layeralignment means and may adhere or may not adhere to each other. It isalso noted that layers that include cell growth may also includepharmacologically active agents.

Once prepared the tubular graft or vessel may be administered to thepatient as a replacement to a damaged vessel or as a scaffolding devicethat can be inserted into or mounted around the damaged vessel. Vasculartubes, known as a STUNT (Support Tube Using New Technology) can be usedfor placement within a blood vessel. Embodiments of the tubular graftshave form memory and will reform if cut or severed back to its originalform and shape. A vessel structure of the present invention will meetthe mechanical and histological requirements of a blood vessel, whileproviding the biological and biochemical functions that are necessaryfor its success. One embodiment that ensures mechanical integrity andbiological compatibility is a scaffold comprising collagen, elastin andheparin. These proteins are the primary components of a typical arterialwall. This will create the natural environment for the endothelialcells, while providing the structural characteristics of these proteins.Endothelialization of the cylindrical matrices will provide the criticalhemocompatibility, while also providing the thrombolyticcharacteristics. This feature will allow for the creation ofsmall-diameter vascular grafts with a reduction in thrombosis.Embodiments of the tubular structure will have a diameter ofapproximately 2-4 mm due to the small-diameters of native coronaryarteries. However, the tubular structure could be any size. Due to theprevalence of coronary disease and the need for effective treatments,the proposed tubular structure would be embraced as a compatiblevascular graft.

Additionally, since the vessels or tubular grafts of the presentinvention are produced with a biocompatible protein and may include thegrowth of cells from the patient or compatible cells, the vessel ortubular graft administered to the host tissue further enhancesacceptance and remodeling of the vessel or tubular graft by the hosttissue. It is again noted that a benefit of the coacervates orbiomaterials of the present invention is the modifying, adapting and/ortransforming of the device into an interwoven and/or functioning part ofthe host tissue.

Furthermore, the vessels and/or tubular grafts may also include one ormore pharmacologically active agents within or attached to thecoacervates or biomaterials that may assist in the facilitation oftissue acceptance and remodeling, as well as inhibit additional adverseconditions sometimes related to implantation of vessels, such asplatelet aggregation, cell proliferation and/or angiogenesis activity,all of which may cause blockage of the vessel. In addition toantiplatelet aggregation drugs, anti-inflammatory agent, gene alteringagents, angiogenesis inhibitors, antiproliferative agents, enzymes,growth factors and other additional pharmacologically active agents canbe included in the vessel and/or tubular graft for localizedadministration to or near the host tissue.

Embodiments of the biocoacervate or biomaterial vessels and/or tubulargrafts may be prepared by methods similar to those described andsuggested above. FIGS. 13 and 14 depict a compression molding devicewherein the inner insert 18 includes a mandrel 29 that extends upwardfrom the insert 18 into the chamber 17. FIG. 14 depicts a top view ofthe compression molding device without the upper insert 19 or plunger14. Following the insertion of a sufficient amount of melted coacervate22 the upper insert 19 and plunger 14 are applied to the coacervate 22.Once cooled, the vessel and/or tubular graft is then removed from thecompression molding device and the vessel or graft is set utilizing acrosslinking technique. The vessel and/or tubular graft generally has awall thickness of approximately 0.05 mm to 1 cm and preferably has awall thickness of 0.15 to 1.5 mm.

In an alternative embodiment, a vessel is prepared by compressingparticles of the present invention into a tubular formation and allowingthe formed tube to dry, thereby setting the structure. FIG. 15 depicts avessel prepared by compressing particles of collagen/elastin/heparin andallowing the compressed particles to dry thereby setting the tublarconfiguration.

Furthermore, other tissue grafts may be made by including in thecompression molding device a cavity 16 and inserts 18 and 19 that areconfigured to produce the size and shape of the tissue graft desired.For example valves such as heart valves; bone; cartilage; tendons;ligaments skin; pancreatic implant devices; and other types of repairsfor tissue that relate to the heart, brain, abdomen, breast, palate,nerve, spinal cord, nasal, liver, muscle, thyroid, adrenal, pancreas,and surrounding tissue such as connective tissue, pericardium andperitoneum may be produced by forming the cavity 16 and inserts 18 and19 of the molding compression chamber into the corresponding size andshape of the particular tissue part. Finally, the tissue grafts may beset by utilizing one or more crosslinking techniques as disclosed orsuggested above. It is noted, that the above mentioned vessels and/ortissue grafts may optionally include one or more pharmacologicallyactive agents or other structural additives, such as metal, insolubleproteins, polymeric and/or biocompatible materials including wire,ceramic, nylon, cotton or polymeric meshes or foams, especially foam,polymer, cotton or fiber tubes.

In another embodiment of the present invention, a containment orfixation device may be prepared utilizing sheets and/or particles, whichinclude the biocoacervate or biomaterials of the present invention. Suchcontainment or fixation devices are generally utilized to assist in thehealing of broken bones, torn tendons, damaged vessels, spinal cordinjury and the like. Examples of such fixation devices are disclosed orsuggested in International Application No. PCT/US03/13273, the entirecontents of which are incorporated by reference herein.

Wound Healing Devices:

Other embodiments of the present invention include wound healing devicesthat utilize the coacervates or biomaterials of the present invention.The wound healing devices may be configured in any shape and size toaccommodate a wound being treated. Moreover, the wound healing devicesof the present invention may be produced in whatever shape and size isnecessary to provide optimum treatment to the wound. These devices canbe produced in the forms that include, but are not limited to, plugs,meshes, strips, sutures, or any other form able to accommodate andassist in the repair of a wound. The damaged portions of the patientthat may be treated with a device made of the coacervates orbiomaterials of the present invention include skin, tissue (nerve,brain, spinal cord, heart, lung, etc.) and bone. Moreover, the woundhealing device of the present invention may be configured and formedinto devices that include, but are not limited to, dental plugs andinserts, skin dressings and bandages, bone inserts, tissue plugs andinserts, vertebrae, vertebral discs, joints (e.g., finger, toe, knee,hip, elbow, wrist,), tissue plugs to close off airway, (e.g., bronchialairway from resected tissue site), other similar devices administered toassist in the treatment repair and remodeling of the damaged tissueand/or bone.

In one embodiment of the wound healing device of the present invention,a coacervate or biomaterial may be formed into a dressing or bandage tobe applied to a wound that has penetrated the skin. An example of anultra-thin collagen/elastin/heparin biomaterial may be approximately 0.1mm in thickness. Generally, the coacervates or biomaterials formed intoa thin dressing or bandage may be approximately 0.05-10 mm in thickness,in a number of embodiments 1-2 mm.

The coacervate or biomaterial wound healing devices, upon application,adhere to the skin and will remain for days depending upon theconditions. If protected, embodiments of the coacervate or biomaterialdressing will remain on the skin for a considerable period of time.Moreover, if the coacervate or biomaterial is acting as a wound dressingand therefore interacting with a wound it will stick very tightly. Thecoacervates or biomaterials of the present invention may also act as anadhesive when wet. It is also noted that the coacervates or biomaterialsof the present invention incorporated into a wound dressing would helpfacilitate or lessen scarring by helping to close the wound.Furthermore, coacervate or biomaterial dressings or bandages may beprepared to administer beneficially healing and repairingpharmacologically active agents, as well as, act as a device that may beincorporated and remodeled into the repairing tissue of the wound.

In another embodiment of the present invention, the coacervates orbiomaterials can also be protected with a tape barrier that is put overthe coacervate or biomaterial and over the wound. A plastic and/oradhesive strip section of material may be used as a tape barrier thatdoes not stick to the coacervate or biomaterial but holds it in placeand provides more protection from the environment. Tape barriers thatare utilized in bandages existing in the art, similar to the BandAid™products, may be used with the dressing of the present invention. FIG.16 depicts a wound dressing comprising a coacervate or biomaterial woundhealing device that is positioned in the center of a non-adhesive stripof material attached to two adhesive ends.

Embodiments of the coacervate or biomaterial wound healing device, alsoprovide a device wherein pharmacologically active agents can be includedwithin or attached to the surface. The coacervates or biomaterials mayinclude, but are not limited to, substances that help clotting, such asclotting factors, substances which are helpful for wound healing, suchas vitamin E, as well as, anti-bacterial or anti-fungal agents to reducethe chance of infection. Other groups of pharmacologically active agentsthat may be delivered by the coacervates or biomaterials are analgesics,local anesthetics, other therapeutics to reduce pain, reduce scarring,reduce edema, and/or other type of drugs that would have very specificeffects in the periphery and facilitate healing. Furthermore, theprotein coacervate or biomaterial interacts with the cells that migrateto the wound to facilitate the healing process and that require ascaffolding and/or blood clotting before they can actually start workingto close and remodel the wound area.

The coacervates or biomaterials of the present invention could alsoassist patients who require more assistance than normal for a wound toactually close. Individuals who have problems with wound healing mayfind that their wound takes longer to close due to their wound not beingable to develop a clot and/or set up a structure for cells to close thewound. In these situations, such as a person with diabetes or ulcers,the coacervates or biomaterials of the present invention may be utilizedto assist in healing. The coacervates or biomaterials provides amaterial that assists the wound in closing, especially if clottingfactors, such as factor 14 and factor 8, and other similar biochemicalsthat are known in the art and are important to wound care are alsoadded.

It is also possible to extend delivery of chemicals or drugs using thecoacervate or biomaterial of the present invention in a layered wounddressing. In one embodiment this can be accomplished by providing wounddressing that includes a patch delivery system adjoined immediatelybehind a layer of the coacervate or biomaterial. In this example astrip, wrap or patch that includes a larger dosage of the chemical orpharmaceutical active component may be applied behind the coacervate orbiomaterial, but not in immediate contact with the wound. Byadministering such a wound healing device, the delivery of chemicalsand/or pharmaceuticals could be extended until the wound was healed orthe desired amount of chemicals and/or pharmaceuticals were applied. Inapplication, the layer of coacervate or biomaterial would continue toabsorb more chemicals and/or pharmaceuticals from the patch as theinitial material impregnated in the coacervate or biomaterial was beingutilized in the wound. Therefore, the coacervate or biomaterial wouldprovide a controlled release of the chemical and/or pharmaceuticalcomponent and would prevent the administration of too much chemicaland/or pharmaceutical component from entering a patient's woundprematurely. Additionally, the coacervate or biomaterial with adjoiningpatch may be very beneficial for patients who are compromised in someway from internally supplying the biological substances needed to reduceor prevent them from healing quickly. Examples of such situations wheresuch a coacervate or biomaterial wound healing device would bebeneficial are in cases of diabetes, hemophilia, other clotting problemsor any other type affliction that inhibits the adequate healing of awound.

Additionally, embodiments of a coacervate or biomaterial dressing thatincludes a patch may be configured to allow a varying controlled releaseof pharmaceuticals through the coacervate or biomaterial by providing alayer system that release molecules at varying rates based on moleculesize. This provides a tremendous means for controlling administration ofmore than one pharmacologically active agent that vary in size. Suchcontrolled release facilitates the administration of pharmaceuticalmolecules into the wound when they may be needed. For example, thecoacervate or biomaterial dressing may be layered with different typesof protein material and biocompatible polymeric material mixtures thatcontrol the release of molecules based on size. For example, each layerof coacervate or biomaterial may include physical and/or chemicalrestraints that slow the migration of various size molecules from thepatch and through the coacervate or biomaterial. Furthermore, the largermolecules that are proteins and other macromolecules that need to be incontact with the wound can be impregnated into the coacervate orbiomaterial itself.

In an alternative wound healing device, as depicted in FIG. 17, abilaminar dressing may include a an Epithelial Cell Migration layer anda Fibroblast/Endothelial Infiltration layer. Particles of the presentinvention may be placed into the wound prior to application of thelaminar dressings to fill in the rough surface of the wound andoptionally deliver pharmacologically active agents. Embodiments similarto these laminar wound healing dressings may assist to retain particlesin the wound, thereby facilitating enhanced healing characteristics. Itis noted that the embodiment depicted in FIG. 17 illustrate the layersof the bilaminated device interacting with keritinocytes (K),fibroblasts (F) and endothelial cells (E).

Furthermore, the coacervate or biomaterial may be set up with pores thatallow fluid flow through that coacervate or biomaterial and alsoenhances movement of the pharmacologically active agents through thecoacervate or biomaterial. Pores may be created in the coacervate orbiomaterial by incorporating a substance in the coacervate orbiomaterial during its preparation that may be removed or dissolved outof the coacervate or biomaterial before administration of the device orshortly after administration. Porosity may be produced in a coacervateor biomaterial by the utilization of materials such as, but not limitedto, salts such as NaCl, amino acids such as glutamine, microorganisms,enzymes, copolymers or other materials, which will be leeched out of thecoacervate or biomaterial to create pores. Other functions of porosityare that the pores create leakage so that cells outside the coacervateor biomaterial can receive fluids that include the contents of thecoacervate or biomaterial and also that cells may enter the coacervateor biomaterial to interact and remodel the coacervate or biomaterial tobetter incorporate and function within the host tissue.

Alternatively, it is also possible to produce a porous coacervate orbiomaterial by the incorporation of a solution saturated orsupersaturated with a gaseous substance, such as carbon dioxide. In oneembodiment, carbonated water may be utilized in a sealed and pressurizedenvironment during the production of the coacervate or biomaterial oradministered when the coacervate is in a melted state. The utilizationof carbonated water creates bubbles within the coacervate or biomaterialduring the production process or when administered in the melted state.Once the coacervate or biomaterial has been solidified, shaped into thedesired form and removed from the sealed and pressurized environment,the gaseous bubbles escape from the coacervate or biomaterial leaving aporous material. In other embodiments, the pores can be produced byintroducing gases, such as air, nitrogen, and the like, via whipping,bubbling, emulsifying, into the melted coacervate to create pores, whichremain in the material after cooling and reformation. For example air ornitrogen may be bubbled or whipped into the melted coacervate whilecooling to form pores. This process can be performed at atmosphericpressure or under applied pressure.

It is noted that the methods of producing a porous material as describedabove may be utilized in any embodiment described in the presentinvention, such as drug delivery devices, tissue grafts and the like.

The coacervates or biomaterials of the present invention may also beutilized as port seals for protrusion devices entering and or exitingthe patient. FIG. 18 depicts one embodiment of a protrusion device 34that includes a port seal 36 comprising a coacervate or biomaterial ofthe present invention. The port seal 26 may be included around the pointof insertion of a protrusion device, such as an electrical lead, a drugdelivery needle or a catheter. Generally, the port seal 36 surrounds theprotrusion device 34 and insulates it from the host tissue. One or moretabs 38 may optionally be included on the port seal 36 to assist in theretention of the protrusion device and further seal the opening in thepatients skin. The tabs 38 may be inserted under the skin or may remainon the outside of the patient's skin. Also, the biocompatible sealcomprising the coacervate or biomaterial of the present inventionprovides stability, reduces the seeping of bodily fluid from around theprotrusion and reduces or prevents immunogenicity caused by theprotrusion device. Furthermore, the port seal may includepharmacologically active agents that may be included to deliveranti-bacterial, analgesic, anti-inflammatory and/or other beneficialpharmacologically active agents.

Other embodiments of the present invention include coacervates orbiomaterials configured and produced as biological fasteners, such asthreads, adhesives, sutures and woven sheets. Threads, adhesives andsutures comprising various embodiments of the coacervate or biomaterialprovide a biocompatible fastening, adhering and suturing function fortemporarily treating and sealing an open wound. Additionally, thebiological fasteners may include pharmacologically active agents thatmay assist in the healing and remodeling of the tissue within and aroundthe wound.

One method of preparing the biocompatible biological fasteners is tomanufacture sheets of coacervate or biomaterial. Once the sheets ofcoacervate or biomaterial are prepared, each sheet may be cut intostrips, threads or other shapes to form sutures, threads and otherbiological fasteners (e.g., hemostats). The sheets may be cut usingcutting techniques known in the art. Also, the coacervate or biomaterialthreads may be woven into sheets and used as strengthened biomaterialweaves that has desired porosity.

Additionally, fibers (large or small, e.g., macro, micro, nano) of aknown suturing material, such as nylon, may be incorporated in thecoacervate or biomaterial when making a sheet of the biomaterial. Oncethe sheet is prepared it may be cut by methods common to the art toproduce a thread/suture that has biocompatible and durablecharacteristics.

Additional embodiments of wound healing devices that include thecoacervate or biomaterial of the present invention include but are notlimited to dental inserts, dental plugs, dental implants, dentaladhesives, denture adhesives or liners and other devices utilized fordental applications. Wounds and dental complications, such as drysocket, present within the interior of the mouth are generally slow toheal, are painful and/or are susceptible to bacterial and other forms ofinfection.

The dental inserts or implants of the present invention may be utilizedto remedy such problems since they are biocompatible with thesurrounding host tissue and may be manufactured to release appropriatepharmacologically active agents that may assist in healing, relieve painand/or reduce bacterial attack of the damaged region. Furthermore, thedental plugs, inserts or implants produced with the coacervates orbiomaterials of the present invention may be incorporated into andremodeled by the surrounding tissue, thereby hastening the healing ofthe damaged region and/or returning the damaged region to its originalstate. For example, dental plugs or implants including the coacervatesor biomaterials of the present invention may be administered to openwounds within the mouth region of the patient following toothextraction, oral surgery or any other type of injury to the interior ofthe mouth to assist in the healing and regeneration of the damagedregion.

In general, the dental plugs, implants or inserts may be administered tothe damaged area by any method known in the art. For example a dentalplug may be administered to the socket of a tooth after removal byplacing a properly sized and shaped dental plug that includes thecoacervate or biomaterial of the present invention into the socket. Thedental plug may optionally be fastened to the surrounding tissue of thesocket by any means known in the art such as adhesives or sutures.However, it may not be necessary to use any fastening means since thecells of the host tissue may be found to readily interact with the plugand begin to incorporate the plug into the host tissue. As previouslysuggested, such a dental plug may also include analgesic antibacterial,and other pharmacologically active agents to reduce or prevent pain andinfection and to promote the reconstruction of the damaged region.

EXAMPLES

The biomaterials and biocoacervates of the present invention will now befurther described with reference to the following non-limiting examplesand the following materials and methods that were employed.

Example 1 Preparation of Biocoacervate

Soluble bovine collagen (Kensey-Nash Corporation) (1.5 gs) was dissolvedin distilled water (100 mls) at 42° C. To this solution was addedelastin (bovine neck ligament, 0.40 g) and sodium heparinate (0.20 g)dissolved in distilled water (40 mls) at room temperature. Theelastin/heparin solution was added quickly to the collagen solution withminimal stirring thereby immediately producing an amorphous coacervateprecipitate. The resulting cloudy mixture was let standing at roomtemperature for 1-2 hrs and then refrigerated. The rubbery precipitateon the bottom of the reaction flask was rinsed three times with freshdistilled water and removed and patted dry with filter paper to yield6.48 gs of crude coacervate (Melgel™ which was then melted at 55° C. andgently mixed to yield a uniform, rubbery, water-insoluble final productafter cooling to room temperature. The supernatant of the reactionmixture was later dried down to a solid which weighed 0.417 g and waswater soluble. The uniform Melgel™ material was used to fabricate bothinjectable compositions for tissue augmentation and biocompatiblestructures for vascular grafts.

Example 2 Biocoacervate Materials Including Additives and pH Solutions

MelGel™ material was prepared as described in Example 1. Nine 1 gsamples of MelGel™ were cut and placed in a glass scintillation vial.The vial was then placed in a water bath at 60° C. and melted. Oncemelted either an additive or pH solution was added to each sample ofMelGel™. The following additives were administered: polyethylene glycol,chondroitin sulfate, hydroxyapatite, glycerol, hyaluronic acid and asolution of NaOH. Each of the above mentioned additives wereadministered at an amount of 3.3 mg separately to four melted samples ofMelGel™ with a few drops of water to maintain MelGel™ viscosity duringmixing. Each of the above mentioned additives were also administered atan amount of 10 mg to another four melted samples of MelGel™ with a fewdrops of water to maintain MelGel™ viscosity. Finally, NaOH was added tothe final melted MelGel™ sample until the MelGel™ tested neutral with pHindicator paper. The uniform Melgel™ material including additives or pHsolution were crosslinked with 0.1% gluteraldehyde for 2 hours and usedto fabricate injectable compositions for tissue augmentation.

Example 3 Preparation of Ground Particles

A sample of Melgel™ was cut into small pieces and treated with aglutaraldehyde (0.1-1.0%) aqueous solution for up to 2 hours. Theresulting coacervate (Melgel™) material was then dried at 45° C. for 24hours and ground to a fine powder and sieved through a 150μ screen. Thispowder was then suspended in phosphate-buffered saline to give a thick,flowable gel-like material which could be injected through a fine needle(23-30 ga.). This formulation is useful for augmentation of facialwrinkles after intradermal injection.

Example 4 Preparation of Homogenized Particles

Samples of Melgel™ as described in Example 2 were cut into small piecesand treated with a glutaraldehyde (0.1%) aqueous solution for 2 hours,was rinsed three times with distilled water, treated with aglycine/glutamine solution for 30 minutes and rinsed again twice withdistilled water. It is noted that other embodiments have been treatedwith 0.2, 0.5 and 1% gluteraldehyde solutions to crosslink the MelGel™.The material was next placed in PBS overnight. The crosslinkedcoacervate (Melgel™) material was removed from PBS solution andhomogenized with a handheld homogenizing polytron to form a wet viscousfine particle mass. The viscous particle mass was then loaded intosyringes, which could be injected through a fine needle (23-30 ga.).This formulation is useful for augmentation of facial wrinkles afterintradermal injection.

Example 5 Preparation of a Vascular Graft

A open-cell polyurethane foam tube was fabricated with an outsidediameter of 6 mm and a wall thickness of 1 mm. This tube was placed intoa container with sufficient coacervate (Melgel) in the melted state tocompletely cover the tube. This combination was placed into a vacuumoven held at 55° C. and a vacuum pulled until trapped air in thepolyurethane tube was removed. The vacuum was released and the Melgelimpregnated tube was cooled to room temperature and placed intodistilled water followed by immersion in a 0.1% aqueous solution ofglutaraldehyde for 2 hours. The resulting tubular graft was thensuitable for use as a replacement vessel graft after appropriatesterilization.

While the invention has been described in conjunction with specificembodiments thereof, it is evident that many alternatives,modifications, and variations will be apparent to those skilled in theart in light of the foregoing description. Accordingly, it is intendedto embrace all such alternatives, modifications, and variations, whichfall within the spirit and broad scope of the invention.

Sequence CWU 1

21159PRTArtificialsynthetic construct similar to silk protein 1Gly AlaGly Ala Gly Ser Gly Ala Gly Ala Gly Ser Gly Ala Gly Ala1 5 10 15Gly SerGly Ala Gly Ala Gly Ser Gly Ala Gly Ala Gly Ser Gly Ala 20 25 30Gly AlaGly Ser Gly Ala Gly Ala Gly Ser Gly Ala Gly Ala Gly Ser 35 40 45Gly AlaGly Ala Gly Ser Gly Ala Ala Gly Tyr 50 5526PRTArtificialseq. repeatedindefinitely, synthetic construct similar to silk protein 2Gly Ala GlyAla Gly Ser1 5371PRTArtificialseq. repeated indefinitely, syntheticconstruct similar to silk protein containing RGD sequence fromfibronectin. 3Gly Ala Gly Ala Gly Ser Gly Ala Gly Ala Gly Ser Gly AlaGly Ala1 5 10 15Gly Ser Gly Ala Gly Ala Gly Ser Gly Ala Gly Ala Gly SerGly Ala 20 25 30Gly Ala Gly Ser Gly Ala Gly Ala Gly Ser Gly Ala Gly AlaGly Ser 35 40 45Gly Ala Gly Ala Gly Ser Gly Ala Ala Val Thr Gly Arg GlyAsp Ser 50 55 60Pro Ala Ser Ala Ala Gly Tyr65 70474PRTArtificialseq.repeated indefinitely, synthetic construct similar to silk proteincontaining sequence from laminin protein. 4Gly Ala Gly Ala Gly Ser GlyAla Gly Ala Gly Ser Gly Ala Gly Ala1 5 10 15Gly Ser Gly Ala Gly Ala GlySer Gly Ala Gly Ala Gly Ser Gly Ala 20 25 30Gly Ala Gly Ser Gly Ala GlyAla Gly Ser Gly Ala Gly Ala Gly Ser 35 40 45Gly Ala Gly Ala Gly Ser GlyAla Ala Pro Gly Ala Ser Ile Lys Val 50 55 60Ala Val Ser Ala Gly Pro SerAla Gly Tyr65 70573PRTArtificialseq. repeated indefinitely, syntheticconstruct similar to silk protein containing a different sequence fromlaminin protein. 5Gly Ala Gly Ala Gly Ser Gly Ala Gly Ala Gly Ser GlyAla Gly Ala1 5 10 15Gly Ser Gly Ala Gly Ala Gly Ser Gly Ala Gly Ala GlySer Gly Ala 20 25 30Gly Ala Gly Ser Gly Ala Gly Ala Gly Ser Gly Ala GlyAla Gly Ser 35 40 45Gly Ala Gly Ala Gly Ser Gly Ala Ala Pro Gly Ala SerIle Lys Val 50 55 60Ala Val Ser Gly Pro Ser Ala Gly Tyr6570671PRTArtificialseq. repeated indefinitely, synthetic constructsimilar to silk protein containing the RGD sequence from fibronectin.6Gly Ala Gly Ala Gly Ser Gly Ala Gly Ala Gly Ser Gly Ala Gly Ala1 5 1015Gly Ser Gly Ala Gly Ala Gly Ser Gly Ala Gly Ala Gly Ser Gly Ala 20 2530Gly Ala Gly Ser Gly Ala Gly Ala Gly Ser Gly Ala Gly Ala Gly Ser 35 4045Gly Ala Gly Ala Gly Ser Arg Tyr Val Val Leu Pro Arg Pro Val Cys 50 5560Phe Glu Lys Ala Ala Gly Tyr65 70720PRTArtificialseq. repeatedindefinitely, synthetic construct similar to elastin protein. 7Val ProGly Val Gly Val Pro Gly Val Gly Val Pro Gly Val Gly Val1 5 10 15Pro GlyVal Gly 20852PRTArtificialseq. repeated indefinitely, syntheticconstruct similar to silk and elastin proteins. 8Gly Val Gly Val Pro GlyVal Gly Val Pro Gly Val Gly Val Pro Gly1 5 10 15Val Gly Val Pro Gly ValGly Val Pro Gly Val Gly Val Pro Gly Val 20 25 30Gly Val Pro Gly Val GlyVal Pro Gly Ala Gly Ala Gly Ser Gly Ala 35 40 45Gly Ala Gly Ser50982PRTArtificialseq. repeated indefinitely, synthetic constructsimilar to silk and elastin proteins. 9Gly Ala Ala Val Pro Gly Val GlyVal Pro Gly Val Gly Val Pro Gly1 5 10 15Val Gly Val Pro Gly Val Gly ValAla Ala Gly Tyr Gly Ala Gly Ala 20 25 30Gly Ser Gly Ala Gly Ala Gly SerGly Ala Gly Ala Gly Ser Gly Ala 35 40 45Gly Ala Gly Ser Gly Ala Gly AlaGly Ser Gly Ala Gly Ala Gly Ser 50 55 60Gly Ala Gly Ala Gly Ser Gly AlaGly Ala Gly Ser Gly Ala Gly Ala65 70 75 80Gly Ser10111PRTArtificialseq.repeated indefinitely, synthetic construct similar to silk and elastinproteins. 10Gly Ala Gly Ala Gly Ser Gly Ala Gly Ala Gly Ser Gly Ala GlyAla1 5 10 15Gly Ser Gly Ala Gly Ala Gly Ser Gly Ala Gly Ala Gly Ser GlyAla 20 25 30Gly Ala Gly Ser Gly Ala Ala Gly Tyr Gly Ala Gly Ala Gly SerGly 35 40 45Ala Gly Ala Gly Ser Gly Ala Gly Ala Gly Ser Gly Ala Gly AlaGly 50 55 60Ser Gly Ala Gly Ala Gly Ser Gly Val Gly Val Pro Gly Val GlyVal65 70 75 80Pro Gly Val Gly Val Pro Gly Val Gly Val Pro Gly Val GlyVal Pro 85 90 95Gly Val Gly Val Pro Gly Val Gly Val Pro Gly Val Gly ValPro 100 105 1101188PRTArtificialseq. repeated indefinitely, syntheticconstruct similar to silk and elastin proteins. 11Gly Val Gly Val ProGly Val Gly Val Pro Gly Val Gly Val Pro Gly1 5 10 15Val Gly Val Pro GlyVal Gly Val Pro Gly Val Gly Val Pro Gly Val 20 25 30Gly Val Pro Gly ValGly Val Pro Gly Ala Gly Ala Gly Ser Gly Ala 35 40 45Gly Ala Gly Ser GlyAla Gly Ala Gly Ser Gly Ala Gly Ala Gly Ser 50 55 60Gly Ala Gly Ala GlySer Gly Ala Gly Ala Gly Ser Gly Ala Gly Ala65 70 75 80Gly Ser Gly AlaGly Ala Gly Ser 8512108PRTArtificialseq. repeated indefinitely,synthetic construct similar to silk and elastin proteins. 12Gly Val GlyVal Pro Gly Val Gly Val Pro Gly Val Gly Val Pro Gly1 5 10 15Val Gly ValPro Gly Val Gly Val Pro Gly Val Gly Val Pro Gly Val 20 25 30Gly Val ProGly Val Gly Val Pro Gly Val Gly Val Pro Gly Val Gly 35 40 45Val Pro GlyVal Gly Val Pro Gly Val Gly Val Pro Gly Ala Gly Ala 50 55 60Gly Ser GlyAla Gly Ala Gly Ser Gly Ala Gly Ala Gly Ser Gly Ala65 70 75 80Gly AlaGly Ser Gly Ala Gly Ala Gly Ser Gly Ala Gly Ala Gly Ser 85 90 95Gly AlaGly Ala Gly Ser Gly Ala Gly Ala Gly Ser 100 10513128PRTArtificialseq.repeated indefinitely, synthetic construct similar to silk and elastinproteins. 13Gly Val Gly Val Pro Gly Val Gly Val Pro Gly Val Gly Val ProGly1 5 10 15Val Gly Val Pro Gly Val Gly Val Pro Gly Val Gly Val Pro GlyVal 20 25 30Gly Val Pro Gly Val Gly Val Pro Gly Val Gly Val Pro Gly ValGly 35 40 45Val Pro Gly Val Gly Val Pro Gly Val Gly Val Pro Gly Val GlyVal 50 55 60Pro Gly Val Gly Val Pro Gly Val Gly Val Pro Gly Val Gly ValPro65 70 75 80Gly Ala Gly Ala Gly Ser Gly Ala Gly Ala Gly Ser Gly AlaGly Ala 85 90 95Gly Ser Gly Ala Gly Ala Gly Ser Gly Ala Gly Ala Gly SerGly Ala 100 105 110Gly Ala Gly Ser Gly Ala Gly Ala Gly Ser Gly Ala GlyAla Gly Ser 115 120 12514208PRTArtificialseq. repeated indefinitely,synthetic construct similar to silk and elastin proteins. 14Gly Val GlyVal Pro Gly Val Gly Val Pro Gly Val Gly Val Pro Gly1 5 10 15Val Gly ValPro Gly Val Gly Val Pro Gly Val Gly Val Pro Gly Val 20 25 30Gly Val ProGly Val Gly Val Pro Gly Val Gly Val Pro Gly Val Gly 35 40 45Val Pro GlyVal Gly Val Pro Gly Val Gly Val Pro Gly Val Gly Val 50 55 60Pro Gly ValGly Val Pro Gly Val Gly Val Pro Gly Val Gly Val Pro65 70 75 80Gly ValGly Val Pro Gly Val Gly Val Pro Gly Val Gly Val Pro Gly 85 90 95Val GlyVal Pro Gly Val Gly Val Pro Gly Val Gly Val Pro Gly Val 100 105 110GlyVal Pro Gly Val Gly Val Pro Gly Val Gly Val Pro Gly Val Gly 115 120125Val Pro Gly Val Gly Val Pro Gly Val Gly Val Pro Gly Val Gly Val 130135 140Pro Gly Val Gly Val Pro Gly Val Gly Val Pro Gly Val Gly ValPro145 150 155 160Gly Ala Gly Ala Gly Ser Gly Ala Gly Ala Gly Ser GlyAla Gly Ala 165 170 175Gly Ser Gly Ala Gly Ala Gly Ser Gly Ala Gly AlaGly Ser Gly Ala 180 185 190Gly Ala Gly Ser Gly Ala Gly Ala Gly Ser GlyAla Gly Ala Gly Ser 195 200 2051576PRTArtificialseq. repeatedindefinitely, synthetic construct similar to silk and elastin proteins.15Gly Val Gly Val Pro Gly Val Gly Val Pro Gly Val Gly Val Pro Gly1 5 1015Val Gly Val Pro Gly Val Gly Val Pro Gly Val Gly Val Pro Gly Val 20 2530Gly Val Pro Gly Val Gly Val Pro Gly Ala Gly Ala Gly Ser Gly Ala 35 4045Gly Ala Gly Ser Gly Ala Gly Ala Gly Ser Gly Ala Gly Ala Gly Ser 50 5560Gly Ala Gly Ala Gly Ser Gly Ala Gly Ala Gly Ser65 70751664PRTArtificialseq. repeated indefinitely, synthetic constructsimilar to silk and elastin proteins. 16Gly Val Gly Val Pro Gly Val GlyVal Pro Gly Val Gly Val Pro Gly1 5 10 15Val Gly Val Pro Gly Val Gly ValPro Gly Val Gly Val Pro Gly Val 20 25 30Gly Val Pro Gly Val Gly Val ProGly Ala Gly Ala Gly Ser Gly Ala 35 40 45Gly Ala Gly Ser Gly Ala Gly AlaGly Ser Gly Ala Gly Ala Gly Ser 50 55 601756PRTArtificialseq. repeatedindefinitely, synthetic construct similar to keratin protein. 17Ala LysLeu Lys Leu Ala Glu Ala Lys Leu Glu Leu Ala Glu Ala Lys1 5 10 15Leu LysLeu Ala Glu Ala Lys Leu Glu Leu Ala Glu Ala Lys Leu Lys 20 25 30Leu AlaGlu Ala Lys Leu Glu Leu Ala Glu Ala Lys Leu Lys Leu Ala 35 40 45Glu AlaLys Leu Glu Leu Ala Glu 50 551815PRTArtificialseq. repeatedindefinitely, synthetic construct similar to collagen protein. 18Gly AlaPro Gly Pro Pro Gly Pro Pro Gly Pro Pro Gly Pro Pro1 5 10151939PRTArtificialseq. repeated indefinitely, synthetic constructsimilar to collagen protein. 19Gly Ala Pro Gly Pro Pro Gly Pro Pro GlyPro Pro Gly Pro Pro Gly1 5 10 15Ala Pro Gly Pro Pro Gly Pro Pro Gly ProPro Gly Pro Pro Gly Pro 20 25 30Ala Gly Pro Val Gly Ser Pro352063PRTArtificialseq. repeated indefinitely, synthetic constructsimilar to collagen protein with a cell binding domain from humancollagen. 20Gly Ala Pro Gly Pro Pro Gly Pro Pro Gly Pro Pro Gly Pro ProGly1 5 10 15Ala Pro Gly Pro Pro Gly Pro Pro Gly Pro Pro Gly Pro Pro GlyLeu 20 25 30Pro Gly Pro Lys Gly Asp Arg Gly Asp Ala Gly Pro Lys Gly AlaAsp 35 40 45Gly Ser Pro Gly Pro Ala Gly Pro Ala Gly Pro Val Gly Ser Pro50 55 602115PRTArtificialseq. repeated indefinitely, synthetic constructsimilar to collagen protein. 21Gly Ala Pro Gly Ala Pro Gly Ser Gln GlyAla Pro Gly Leu Gln1 5 10 15

1-12. (canceled)
 13. A biomaterial comprising an amorphous material thatis crosslinked with one or more crosslinking agents, the amorphousmaterial including aggregated complexes having homogenously distributedbiocoacervated components, the components comprising one or more solubleor solubilized primary proteins combined with one or moreglycosaminoglycans and one or more biocompatible solvents.
 14. Thebiomaterial of claim 13 wherein the one or more primary proteins areselected from the group consisting of collagen, laminin, bonemorphogenic protein and its isoforms that contain glycosaminoglycanbinding sites, albumin, interleukins, epidermal growth factors,fibronectin, thrombin, aprotinin and antithrombin III.
 15. Thebiomaterial of claim 13 wherein the one or more glycosaminoglycans areselected from the group consisting of heparin, heparin sulfate, keratansulfate, dermatin, dermatin sulfate, heparin-hyaluronic acid,chondroitin, chondroitin sulfate, chondroitin 6-sulfate, chondroitin4-sulfate, chitin, chitosan, acetyl-glucosamine, hyaluronic acid,aggrecan, decorin, biglycan, fibromodulin, lumican and complexesthereof.
 16. The biomaterial of claim 13 further comprising one or moresecondary proteins.
 17. The biomaterial of claim 16 wherein the one ormore secondary proteins are selected from the group consisting offibrin, fibrinogen, elastin, albumin, ovalbumin, keratin, silk, silkfibroin, actin, myosin, thrombin, aprotinin and antithrombin III. 18.The biomaterial of claim 13 wherein the one or more biocompatiblesolvents are selected from the group consisting of water, dimethylsulfoxide (DMSO), biocompatible alcohols, biocompatible acids, oils andbiocompatible glycols.
 19. The biomaterial of claim 13 furthercomprising one or more pharmacologically active agents.
 20. Thebiomaterial of claim 19 wherein the one or more pharmacologically activeagents are selected from the group consisting of analgesics,anesthetics, antiproliferative agents, angiogenesis inhibitors,antipsychotic agents, angiogenic growth factors, bone mendingbiochemicals, steroids, antisteroids, corticosteroids, antiglacomaagents, antialcohol agents, anti coagulant agents, genetic material,antithrombolytic agents, anticancer agents, anti Parkinson agents,antiepileptic agents, anti inflammatory agents, anticonception agents,enzymes agents, cells, growth factors, antiviral agents, antibacterialagents, antifungal agents, hypoglycemic agents, antihistamine agents,chemoattractants, neutraceuticals, antiobesity, smoking cessationagents, obstetric agents and antiasmatic agents.
 21. The biomaterial ofclaim 19 wherein the one or more pharmacologically active agents areselected from the group consisting of paclitaxol, sirolimus, estradiol,demopressin, dexamethazone, bone morphogenic protein, vitamin D, vitaminE, vitamin A, vitamin C, vitamin B, stem cells, superoxide dismutase,VEGF, FGF, EGF, sufentanil, fentanyl, capsaicin, lidocaine bupivacaine,benzocaine, testosterone and cortisone.
 22. (canceled)
 23. Thebiomaterial of claim 13 wherein the biomaterial further includes one ormore biocompatible additives selected from the group consisting ofepoxies, polyesters, acrylics, nylons, silicones, polyanhydride,polyurethane, polycarbonate, poly(tetrafluoroethylene),polycaprolactone, polyalkenes, polyacrylates, bioceramic materials,polyethylene oxide, polyethylene glycol, poly(vinyl chloride),polylactic acid, polyglycolic acid, polypropylene oxide,poly(alkylene)glycol, polyoxyethylene, sebacic acid, polyvinyl alcohol,2 hydroxyethyl methacrylate, polymethyl methacrylate, 1,3bis(carboxyphenoxy)propane, lipids, phosphatidylcholine, triglycerides,polyhydroxybutyrate, polyhydroxyvalerate, poly(ethylene oxide), polyortho esters, poly (amino acids), polycyanoacrylates, polyphophazenes,polysulfone, polyamine, poly (amido amines), glycosaminoglycans,bioceramic materials, insoluble proteins, proteins, amino acids, oils,fatty acids, salts, sugars, polypeptides, peptides, humectants, fibrin,graphite, flexible fluoropolymer, isobutyl based, isopropyl styrene,vinyl pyrrolidone, cellulose acetate dibutyrate, silicone rubber, andcopolymers of these.
 24. The amorphous biomaterial of claim 13 whereinthe biomaterial further includes one or more additives selected from thegroup consisting of hyaluronic acid, chondroitin sulfate, glycine,glutamine, calcium carbonate, calcium sulfate, magnesium sulfate,glucose, ribose, alginate, collagen, elastin, laminin, hydroxyapatite,polyethylene glycol, glycerol, sodium hydroxide and potassium hydroxide.25. The biomaterial of claim 13 wherein the one or more crosslinkingagents are selected from the group consisting of glutaraldehyde,1,4-butandiol diglycidylether, formaldehyde, glyoxal, sebacic acidbis(N-succinimidyl)ester (DSS), p Azidobenzolyl Hydazide, N 5 Azido 2nitrobenzoyloxysuccinimide, N Succinimidyl 6 [4′azido 2′nitrophenylamino]hexanoate and 4 [p Azidosalicylamido]butylamine.
 26. Thebiomaterial of claim 13 wherein the biomaterial is processed in a formselected from the group consisting of a coating, cylinder, wafer, bar,sphere, capsule, vessel, tubular graft, particles, biomesh, plug, sheetand valve.
 27. The biomaterial of claim 13 wherein the primary proteinsinclude collagen, the glycosaminoglycan is selected from the groupconsisting of hyaluronic acid, heparin and condroitin sulfate, thesecondary proteins include elastin and the biocompatible solventincludes water.
 28. An amorphous thermoplastic biocoacervate comprisingan amorphous material having thermoplastic properties and includingaggregated complexes having homogenously distributed biocoacervatedcomponents, the components including one or more soluble or solubilizedprimary proteins combined with one or more glycosaminoglycans and one ormore biocompatible solvents.
 29. The biocoacervate of claim 28 whereinthe one or more soluble or solubilized primary proteins are selectedfrom the group consisting of collagen, laminin, bone morphogenic proteinand its isoforms that contain glycosaminoglycan binding sites, albumin,interleukins, epidermal growth factors, fibronectin, thrombin, aprotininand antithrombin III.
 30. The biocoacervate of claim 28 wherein the oneor more glycosaminoglycans are selected from the group consisting ofheparin, heparin sulfate, keratan sulfate, dermatin, dermatin sulfate,heparin-hyaluronic acid, chondroitin, chondroitin sulfate, chondroitin6-sulfate, chondroitin 4-sulfate, chitin, chitosan, acetyl-glucosamine,hyaluronic acid, aggrecan, decorin, biglycan, fibromodulin, lumican andcomplexes thereof.
 31. (canceled)
 32. The biocoacervate of claim 28wherein the biocoacervate further includes one or more secondaryproteins selected from the group consisting of fibrin, fibrinogen,elastin, albumin, ovalbumin, keratin, silk, silk fibroin, actin, myosin,thrombin, aprotinin and antithrombin III.
 33. The biocoacervate of claim28 wherein the one or more biocompatible solvents are selected from thegroup consisting of water, dimethyl sulfoxide (DMSO), biocompatiblealcohols, biocompatible acids, oils and biocompatible glycols. 34.(canceled)
 35. The biocoacervate of claim 34 wherein the biocoacervatefurther includes one or more pharmacologically active agents selectedfrom the group consisting of analgesics, anesthetics, antiproliferativeagents, angiogenesis inhibitors, antipsychotic agents, angiogenic growthfactors, bone mending biochemicals, steroids, antisteroids,corticosteroids, antiglacoma agents, antialcohol agents, anti coagulantagents, genetic material, antithrombolytic agents, anticancer agents,anti Parkinson agents, antiepileptic agents, anti inflammatory agents,anticonception agents, enzymes agents, cells, growth factors, antiviralagents, antibacterial agents, antifungal agents, hypoglycemic agents,antihistamine agents, chemoattractants, neutraceuticals, antiobesity,smoking cessation agents, obstetric agents and antiasmatic agents.36-40. (canceled)